Qt assistant clears help collection FilePath location when trying to update the cached location of .qhc

Our application installs Qt Assistant as a custom help viewer. Our installer installs Qt Assistant and the .qhc and .qch files in a directory within our app directory let's say C:\Perforce\Resources\help.

After starting our app and starting QtAssistant a copy of the .qhc files is installed in the cached location. Upon examining the Namespace table in the .qhc file the .qch FilPath is something like ../../../../../../Program Files/Perforce/P4VResources/p4vhelp/p4vhelp_en.qch

Then I uninstall our product (leaving the cached files alone.

Now, I install our product again, but this time in the D: drive.
After this our help no longer works and it can't find the documentation.
The FilePath in the cached location was updated and it is now empty, which explains why it no longer works.

You should be able to reproduce the above steps by downloading P4V from our website www.perforce.com
Steps to repro:
1. Clear Perforce/P4V cache
2. Install P4V in C: drive
3. Start P4V and invoke help - assistant starts and cache file is created.
4. Uninstall P4V - leave cache location alone
5. Install P4V in the D: drive
6. Start P4V and help no longer works.

Since I'm re-installing the same version on another location it doesn't seem necessary to uninstall the cache file and lose all the settings.
Please let me know if you are able to reproduce this problem.

Kind regards,
Chris Renck