On a lower end system, especially with a brand new (or repaired, etc.) installation of .NET, 5-7 minutes is perfectly normal.
Incidentally, what counts as a "lower end system" for the purposes of this software? It took the 3.20a installer about twenty-five minutes to finish optimizing, running on a 2000 GHz 64-bit Athlon with 1GB RAM. No other programs were running until the last five or ten minutes, when I loaded Firefox to check to see if this was a known bug in the alpha! (It has finished now and the program is running fine, I'm just curious as to whether this is anomalous.)