Well, I already posted that on maniaplanet-forum, but i still would like to post it here, and maybe add new issues, bugs and problems you noticed.
Here are a few i noticed (i know, some of them has been already posted here).

1) thousand blocks? Lol, i just see thousand reflected blocks, but as Gekko in another post said: all the maps looks the same to my eyes, you only see different combinations between blocks. Why? Because basically, we only have a bunch of blocks.

2) In tmuf and tmn, you could directly open gbx files without putting them in the maniaplanet-> tracks directory. You could directly "download-> open" the map. And now, tell me why in this brand NEW game, we can't do that! Fortunately, ManiaExchange and Ichoru, elaborated 2 different systems to avoid that lack of "compatibility with gbx files. But the problem still exist with replays.

3) Media tracker? Lol, some new and nice functions, but wtf, why to import a replay in the map,do we have to save it as a clip, and then import it in mediatracker?

4) Time-speed, ok really nice function, but tell me, what's his use if i can't:
-Use it in a video (yes, you see it ingame, but once you render the video, the time-speed doesn't work/shows
-Use it in a Map intro or Map ingame mt work, it work once you're doing it in the ingame-mt work, but when you play the map, there are no time-speed variations. Only normal "speed".

5) In tmnf/tmuf, when we drived a map offline, and forgot to save the replay just after the run, we could still save it by pressing the little "timer" just in the top left side of the screen.
Where's this funcion in canyon?
5b) In tmnf/tmuf, when we drived a map online, and then, played it offline in solomode (after download from tmx), we still could save our replay driven online, just by pressing the little timer in the top-left side of the screen.
Where's this function in canyon?

..more to come...

Please, if you found other lacks of function comparing to tmuf/tmnf post them here!

connected with 5th: there are no online autosaves! even though it was in beta. and when playing offline I miss author/gold/silver/bronze times in top left corner.
another things I'm missing in TM² are water bumps and splashes. maybe bumps aren't that real, but why no splashes?! and there's even a sound of them!

About nr 2: you can re-install the game and then the auto start works, for me it works, but i must choice tm2 or tmu the one i install last will be auto start on. but now i can have auto on tmu and use "install and play" for tm2. but now you dont need to becouse Forzyy added
a feature "install and play" it almost work the same way..

On #3, you can record directly in the media tracker, no need to import replays unless you are adding aircraft or watercraft, or are adding traffic coming from a location other than the regular starting line.

Unless they removed that feature...

Add to 3: When you edited an outro in TMF, the last validation replay was present. It made adding custom cameras with anchors and targets easy. You (at least I) can't seem to do this any more. I always have to import a media tracker ghost into the clip/trigger I'm editing and delete it once I'm done. I find it really annoying and time consuming (yeah, yeah, a couple more clicks etc.).

Agree i also miss ghost import very enoying, and the solo autosave

fun to play against you pb and se where the error lies.

Forzyy says:
Add to 3: When you edited an outro in TMF, the last validation replay was present. It made adding custom cameras with anchors and targets easy. You (at least I) can't seem to do this any more. I always have to import a media tracker ghost into the clip/trigger I'm editing and delete it once I'm done. I find it really annoying and time consuming (yeah, yeah, a couple more clicks etc.).

No, you just need to make a mediatracker ghost during your current session.

But yes, I agree this game is a downgrade of a five year old free title and I'm puzzled as to why it has to cost €20 when the exact same game with strictly more features costs €0.