Playing Mutant Mudds Deluxe in online / offline mode

There is a big in-game difference between playing Mutant Mudds Deluxe being in Steam online / offline mode. If you know that, this could avoid you some bad surprises.

Just be careful if you play Mutant Mudds Deluxe in offline mode...

Saves won't be affected, but achievements will not be unlocked during the game. After that, you can't do anything to get them back, because autosave cancel any backward possibility. The only way to do this is starting a new game, and do again what you did to get the achievement. So be careful...
This is based on personal experience.

[D.A.R.K.]

After finish the game once you just can play it all again and do those Achievements that you couldn't in the firs time.

PS.: All games on Offline mode will not save anything that is based on connection, as Achievements and Cloud Save/Load games.

[whereisthecat]

Earned Your Allowance didn't unlock when I played offline. So I had to finish the game twice to get all achievements.

[VinchenzoTheJackal & Shoon]

Which acheivements are effected? I was able to quickly unlock 3 acheivements even though I reached outer space in my game solely by playing offline. I'm not sure which acheivements I've missed that I cannot unlock on my save, and which I can still redo on my save...
I was able to do the following acheivements:
Beat a level without dieing, beat a level without getting hurt, beat a level without checkpoints.