Thanks for the tips, Ascensi. It seems the best we can do for now is using alternatives.
It would be nice, though, to have at least a word from RL as to what is to be expected in the future, unless they have no idea themselves...
Forgot to mention, if you use the newest version of Meshlab, you can download the Collada files from the 3d Warehouse then open it in meshlab and then export it to obj etc.
Try https://www.meshlab.net/ to clean and convert your files, I don't see any activity from Reallusion updating 3DXChange unfortunately. I hope that helps.
Thanks for your support, Dennis!
It is waaaaay past time to address this issue.
It is now 2021, and we can't even open a 5-year old file saved in the year 2016?
And we are still stuck in 32-bit mode too.