Impact of ActiveSky on FPS

Hello, I run XP Pro, 1Gbyte memory, Pentium 2.4, GF4 TI 4600 128 Mb, FS2002 PRO.First of all ActiveSky is a GREAT product. I have observed that when ActiveSky "processes" a METAR my FPS drops from 40 to 10-13 FPS (depending , I think, on the clouds defined in SkyWorld)and this for 5 to 10 seconds, sometime more.How can I improve the performance on my PC or ActiveSky to avoid the drop of FPS?Emile EBBR