Uninstalling and reinstalling CS6 - can't make it work

I have PS CC18 but have retained CS6 Master Suite on my Mac, as I use other programmes and want to keep access to Photoshop CS6 should I need it in the future. I was having a problem with defaults trying to open my files in CS6 instead of CC, so I decided to delete the old version and force the system to recognise Creative Cloud as the default.

However, my PS CS6 won't open, I get a 'Configuration Error - Error 1' and instructions to uninstall and reinstall the product.

I have no uninstall option in the folder, so I've tried downloading PS CS6 from Adobe and reinstalling - that gives me an error as follows: Installer failed to initialize. This could be due to a missing file. Please download Adobe Support Advisor to detect the problem. However, it seems the Adobe Support Advisor is now defunct.

I've tried downloading the whole CS6 Master collection, and reinstalling the whole lot, (both in normal and safe mode). That overwrites many of the products but fails on Photoshop and gives me the following error summary:

Exit Code: 6

Please see specific errors below for troubleshooting. For example,  ERROR: DF024 ...

-------------------------------------- Summary --------------------------------------

- 0 fatal error(s), 1 error(s)

----------- Payload: Adobe Photoshop CS6 Core 13.0.0.0 {9124DF4E-617D-486B-A970-8FA632244F24} -----------

ERROR: DF024: Unable to preserve original file at "/Applications/Adobe Photoshop CS6/Adobe Photoshop CS6.app/Contents/Frameworks/AdobeCrashReporter.framework/AdobeCrashReporter" (Seq 94)

-------------------------------------------------------------------------------------

System Requirements

I've tried using the Cleaner tool - that didn't help.

I've tried uninstalling the whole CS6 collection using Utilities>Adobe Installers, but that fails and gives me the following report:

Exit Code: 33 Please see specific errors below for troubleshooting. For example, ERROR: DW040 ... -------------------------------------- Summary -------------------------------------- - 0 fatal error(s), 1 error(s) ERROR: DW040: The product "{41C543D4-AC29-4B7E-B95D-D73B7EB2EFBB}" is not installed. Cannot proceed with the uninstall -------------------------------------------------------------------------------------

System Requirements

I've spent hours going round in circles and not achieving anything. Can anyone offer any suggestions?

Thanks very much.