I've tried a few things post-update;
User created items in multi-environment maps do show textures now!
Selecting multiple replays to race does load all selected now!
Many other things seem to be working correctly now too.
[However]:
Record Mediatracker Ghost acts like a Validation run and ends with "Validate & Save" or "Retry" but no save replay option or automatically showing replay, however you can edit end of race media after. Also it (mediatracker) still doesn't show your current lap on multi lap races.
~Ironically I also ran the old Trackmania² Title and those two things worked fine in it. In fact I can't seem to find any issues when using the old TM² Title. Of course I've only spent about an hour checking things out and it does still use the older interface.
All in all, I must say, I am liking this latest update very much.
Thank you Nadeo!