after many hours working on a NI Massive sound i save the preset, and then when I open the sonar X2 project its all flat again... Does anybody know a solution for this issue?

I'm not sure - but what I'd do next is run Massive in Standalone Mode and try a few quick simple tweaks on a sound you don't really care too much about and see if it happens there first.

If so, then it's isolated to Massive as opposed to a Sonar issue.

Next, after saving that new edited sound, open Sonar, insert Massive, and make sure that sound is the same as it was in Stand alone mode.

Try saving the whole thing & reopening it all then.

I always have a few pretty weird issues with NI Massive myself! Not sure if it's the software itself that's buggy 'til the next update, or if it's not so compatible with SONAR; though I don't know why I'm inclined to go for the latter. Problems tend to present themselves when projects start getting a bit CPU and RAM intensive. One example of a problem I've had recently is the sound coming from the synth (whether I've tweaked it or not, although I usually do and a lot) completely changing or totally distorting and 'muddying up'. This usually happens not when I'm tweaking the sound itself, but when I'm adding more processing to other tracks, or in general working on the project. The sound then stays this way permanently unless I return to the previous save point, before whatever further processing I did (not necessarily to the Massive midi track itself) caused it to go awry. Has this happened to you as well?

not really, that could be lack of ram

+1 for running in standalone mode first, you should do this with all of NI's stuff to avoid problems. 

The only other thing I would suggest is making sure it's updated to the latest version via the Native Instruments Service Center. 

JPPG
not really, that could be lack of ram

I see you have 4GB of RAM; I have 12GB... Hmm