it's does suggest that something is not being done correctly in Media Portal.
Then have a look at the source, and try and help.
I'm lucky in respect of i see whats going on in the background, and a lot of these guys are working every day\night together updating\testing to get things right for possibly a worldwide audience.
ps. wish we could do a M$ and say to manufacturers\consumers "meet our specs or we will not support you", half if not more of the problems we encounter are down to hardware installation problems\drivers\codecs, not MP itself, so comparing Mediaportal directly to MCE (which i have) which also crashes and closes itself down, is not a valid and fair comparison.