The MB manual tranny used in the XFire is not world-renowned for smooth shifts, particularly 1st to 2nd, so it's the trans, not you.
Try replacing the tranny fluid with 5W-20 syn engine oil and see if that helps. Think there was an early TSB on early XFire trannys for popping out of gear and rough getting into reverse, but good luck finding a dealer that will know how to do it.
Do a search on "manual transmission fluid" and you'll see that you're not the Lone Ranger in terms of rough shifting issues. Here's one of many....
https://www.crossfireforum.org/forum...smission+fluid