I made a save points at:
-end of mission 3 on Supersoldier difficulty
-end of mission 7 on Supersoldier difficulty
at the end of mission 3, you'll need to kill 4 baddies (or sneak past them) and climb the stairs and activate the console
at the end of mission 7, you'll have to blast an enemy space ship using the space laser
The Supersoldier achievements are glitched, so it may not unlock for you. For me these achievements unlocked:
-Nanosuit veteran - complete 3 of 7 mission on veteran difficulty
-Bring it on - complete campaign on veteran difficulty
-Professional Superhero - complete campaign on Supersoldier difficulty
however, I can not get "Halfway to Hell" (complete 3 of 7 mission on Soldier difficulty) to unlock.
Other achievement I got on my first Normal difficulty playthrough - they may also unlock with the save files
I also made a save file for "Suited Up" (upgrade all nanosuit modules to max). Choose replay mission, and replay mission 3 (Root of All Evil). After a very short time, your AI buddy will open up an elevator shaft. You have to jump in it to progress the story. The elevator will drop and you end up in water. Select the nanosuit module for swimming 1000m (the one without the star, on the left column) and swim around in the water and the achievement should unlock.
I included the content cache along with the save file - not sure if they are needed, or if they even work. They were initially 2mb in size, but after I removed my profile id and saved them, the file size shrunk drastically.
If these do not work, or if I stuffed up along the way, my apologies in advance.
Crysis 3 achievement saves.rar