I have attempted to run the 4.0.0.4 and 4.0.1.0 builds of x2goclient on my MacBook Pro (OS version 10.7.3). Both of them crash immediately on launch. When attempting to run from the command line I get illegal instruction 4. Unfortunately, I have not used a Mac long enough to know how to troubleshoot this (though I do have an extensive UNIX/BSD/Linux background) beyond the basics outlined below.
For the 4.0.1.0 build, I have verified the md5 sum matches. I have the .dmg files for the 4.0.1.0 and 3.99.2.1 builds mounted. One thing I notice is that 4.0.x is significantly smaller than 3.99:
/dev/disk1s2 50272 50272 0 100% /Volumes/x2goclient /dev/disk3s2 223104 188328 34776 85% /Volumes/x2goclient 3.99.2.1
Are the newer builds expected to be this much smaller? Unpacked, the entire dmg for 4.0.x is about 70MB smaller than the actual space used by 3.99.x, even with the dmg for 3.99 being somewhat bigger than the amount of space required.