You can set the color (and opacity) of the caption area's background. In fact, you can set a different color and opacity for the top and bottom of the caption area's background independently of one another so that you have a gradient effect (which is actually the default setting).
You'll find the captionBackColor and captionBackTopColor configuration options in JuiceboxBuilder-Pro's 'Customize -> Color' section. (An opacity of 0 is fully transparent and an opacity of 1 is fully opaque.)

Alternatively, you can move the captionPosition (in JuiceboxBuilder-Pro's 'Customize -> Caption' section) to a non-overlay value such as BELOW_IMAGE, BELOW_THUMBS or BOTTOM so that the caption text is not overlaid on top of the image.

I hope this helps.

You're welcome!

I'm sorry to heat that you are having trouble installing JuiceboxBuilder-Pro on a Windows 7 computer.
JuiceboxBuilder-Pro should work fine under Windows 7.

Here are a few hints and tips (although you might already have tried most or all of them).

#1 Check out the Install Issues in the JuiceboxBuilder User Guide in case any of the notes describe the problem you are facing and help.

#2 If using MacOS Catalina (10.15), then please see the additional steps required to install JuiceboxBuilder-Pro here.

#3 Make sure that you are using the latest version of JuiceboxBuilder-Pro (v1.5.1).
If necessary, full instructions for downloading the latest version can be found on the Upgrading Juicbebox support page.

#4 Make sure that you have extracted the 'juicebox_pro_1.5.1.zip' file to your hard drive (rather than just looking inside the file with a zip program) and that you are not running the 'JuiceboxBuilder-Pro.air' file from a restricted file system or network drive.

#5 Make sure that the 'juicebox_pro_1.5.1.zip' and 'JuiceboxBuilder-Pro.air' files are not corrupt.
(If you have been able to extract the 'juicebox_pro_1.5.1.zip' file without any errors, then the chances are that your files are OK.)

Name: juicebox_pro_1.5.1.zip
Filesize: 1,912,372 bytes
MD5: 684b9d42be40906ac775aecfbb8631d8
SHA1: 872bcd0b62ef9841eab672e6a12f431919a4d969

Name: JuiceboxBuilder-Pro.air (v1.5.1)
Filesize: 1,390,776 bytes
MD5: 1030cd51905c5e432f4d57a7bfa4e203
SHA1: 0790b8df79efaf6f0b89624884252fd07001149e

You can check the MD5 and SHA1 hashes of files with a free program such as HashCalc.

#6 Make sure that you are using the latest version of Adobe AIR (v32.0).
If necessary, the latest version can be downloaded from the Adobe AIR download page here.

#7 Check out the "Troubleshoot Adobe AIR installation" help pages below in case the problem is with Adobe AIR (rather than with JuiceboxBuilder-Pro).
Mac: https://helpx.adobe.com/air/kb/troubles … ac-os.html
Windows: https://helpx.adobe.com/air/kb/troubles … ndows.html

#8 Try using an older version of Adobe AIR.
JuiceboxBuilder-Pro requires Adobe AIR v2.0 or later so you could try a version such as v13.0 which you can download from the Adobe AIR archive download page here.
(I would not normally recommend using an old version of any software but it might be worth trying to see if it makes a difference.)

#9 Try completely disabling any third-party security software that you might have installed (e.g. Avast or AVG), including real-time protection and ransomware detection, before attempting to install JuiceboxBuilder-Pro in case this may somehow be interfering the JuiceboxBuilder-Pro installation.
(Please do so at your own risk and be sure to disconnect from the internet first.)

#10 Check that your system clock is accurate (and resync with a known time server if necessary) before attempting to install JuiceboxBuilder-Pro. (One user actually claims to have had to wind back his system clock 2 years in order to install JuiceboxBuilder-Pro. This seems to have been an isolated incident and no-one is quite sure why this was necessary but it might be something worth trying if nothing else works.)

#11 Try the complete uninstall/reinstall procedure below.

(1) Uninstall your current version of JuiceboxBuilder-Pro (if you have a version installed).
Mac: Delete the 'JuiceboxBuilder-Pro' file from the Applications folder and empty your Trash.
Windows: Use the uninstaller in the 'Control Panel -> Programs -> Uninstall a program...' list.

(2) After uninstalling JuiceboxBuilder-Pro, please check that there are no files are left behind (even from a failed installation) by manually deleting the following folders (if they exist) from your hard drive:
Mac:
/Applications/JuiceboxBuilder-Pro.app/
/Users/Username/Library/Application Support/Adobe/AIR/ELS/JuiceboxBuilder-Pro
/Users/Username/Library/Preferences/JuiceboxBuilder-Pro
Windows:
C:\Program Files (x86)\JuiceboxBuilder-Pro
C:\Users\Username\AppData\Roaming\Adobe\AIR\ELS\JuiceboxBuilder-Pro
C:\Users\Username\AppData\Roaming\JuiceboxBuilder-Pro
C:\Users\Username\Documents\JuiceboxBuilder-Pro
You may need to show hidden files to find some of the above locations in Windows File Explorer.

(3) Also, please follow the procedure above (Steps #1 - #2) for JuiceboxBuilder-Lite, too (if you have it installed).
JuiceboxBuilder-Lite and JuiceboxBuilder-Pro can both be installed and run side by side on the same computer but, being that you are experiencing problems, it might be wise to completely clear your system of all JuiceboxBuilder files before trying to reinstall JuiceboxBuilder-Pro.

(4) Uninstall Adobe AIR.

(5) Reinstall Adobe AIR.
You can download the latest version of Adobe AIR (v32.0) from here.
Windows: To install Adobe AIR, instead of just double-clicking the 'AdobeAIRInstaller.exe' installation file, right-click it and select 'Run as administrator'.

(6) Reinstall JuiceboxBuilder-Pro (making sure that it is the latest version, v1.5.1) following the instructions here.

I hope my notes above help.
If you continue to experience difficulties, then please let me know what error message(s) you encounter and, if possible, attach your Adobe AIR log file (C:\Users\Username\AppData\Local\Adobe\AIR\logs\Install.log) to a post so that I can take a look at it and hopefully help further.
Thank you.

You're welcome. I'm sorry to hear that you have not yet been able to resolve your problem., though.
Did all of the above carefully, step by step. I've probably used up my 5 download limit trying to solve this.
Don't worry about the 5 download limit. If your link expires, just fill in the Download Link Request Form and we'll send you a new one (there is no limit to how many times you can fill in the form).

Thank you for providing your log file. It is very strange that you encounter a "Package signature validation failed" message.
I have just completely uninstalled (manually removing all related files after the uninstallation process) and reinstalled JuiceboxBuilder-Pro on my own Windows 10 computer and it worked fine.

That is, however, the same message that the user who had to wind back his system clock a couple of years to install JuiceboxBuilder-Pro received so, if you have not yet tried this odd suggestion, then it might be worth trying.

Another suggestion that I did not mention in my notes above is to try an older version of Adobe AIR.
I would not normally recommend using older software but, in the absence of knowing exactly what is causing your problem and in the interest of getting JuiceboxBuilder-Pro up and running, it is something that I'd try myself.
JuiceboxBuilder-Pro requires Adobe AIR v2.0 or later so you could try a version such as v13.0 which you can download from the Adobe AIR archive download page here.

(I've added this in my post above just so my post above is complete with all known suggestions so that I can refer other users to the post if necessary.)

I hope these additional notes/suggestions help.