But yeah, try deleting your temp folder and then relaunching your DAW (or properly reloading Nebula).
Some programs load faster than others because of the amount of samples they contain.
And if you're loading 96k programs into a 44/48/88 project, the samples will have to be resampled (which means CPU time).
If there is no resampling being done, the only thing affecting load time is harddisk speed (which can make a huge impact with some nebula programs being a few hundred megabyte ).
I have some long programs that take +/- 3 seconds to load, on a Core i7-860 overclocked. But those are the few programs that take that long, none take longer and most are within 0.5 second so to speak. (not using a SSD drive, but using a raid0 array with two fast harddrives to get faster sequential transfer rates. If the partition is properly defragged it helps a lot. SSD would've been better though, but my Nebula library is quite huge ).