V-PlaySamplelauncher.sh does not run. The LD_LOAD_PATH environment variable doesn’t work as you intended, apparently. I ran strace -eopen and looked at the library search, and it never traversed the contents of LD_LOAD_PATH. I skipped this and moved on to trying to run one of the demos directly.
All of the demos fail with missing includes. QApplication, VPApplication, QQmlApplicationEngine, just depending on which demo. I haven’t gotten a single one of your .pro files to build.
I don’t have any spaces in my path. I installed everything from scratch yesterday, and if the installation is corrupted, your installer is broken. I checked for updates just now, and there were none.
I put a lot of effort into this, and I have found this experience severely disappointing.