Does the Online Installer mess up my existing Qt versions?

[Asperamanca]

I have several handcrafted Qt versions on my machine that are only slightly less important for my work than a continuous supply of oxygen.
Before I try out the new online installer, are there any steps to ensure nothing of my existing Qt installations is touched?

[JKSH]

Hi,

Simply tell the online installer to install files in a new directory, away from existing installations. The online installer will only touch that directory. The rest of your system, including existing Qt versions, will be untouched.

Note: In a system which contains multiple versions of Qt, make sure you do not add any version of Qt to your PATH. This avoids the risk of linking your programs against the wrong version.

[Asperamanca]

Thanks! Took your advice, and detected no ill effects so far.

[Asperamanca]

Suddenly, my Visual Studio 2010 crashes every time I open any of my solutions (all C++). I can't pin this on the Qt installation for sure, but there's nothing else unusual I changed.

Nothing I tried so far has solved this for me (delete sdf+ilk files, delete suo file, disable all extensions, unload add-ins, run in safe mode).
I originally planned to use the newer Qt versions in Studio, so I installed the 5.3.2 and 4.8.6 for Studio 2010, but I have uninstalled them since.

Edit:
Seems to work after a reboot. That was scary.