No problems since sr2.1 have not tried the new sr3 patch yet. I've upgraded my machine 3 times since Poser 5 came out have'nt had any problems on any of them.

original machine specs: (No Probs.) (retired MB Exploded)
P3 1Ghz 512 Megs Ram
Abit SA6R Motherboard
4 80 gig HDs
Pioneer Slot loading DVD-ROm 16X
Yahmaha 12x CDR 8x CDRW 24X read Cd-rom
Nvidia (Pny) Geforce 4 4600 TI 128 megs ram
SB Live! Plat. Sound Card
Win XP Home (NTFS Format)

2nd Machine specs: (No Probs.) (Now just used for games)
P4 3.06Ghz (Overclocked to 3.418Ghz) 1 Gig DDr 3500 Ram
ASUS P4G8X Motherboard
1 120 gig 4 80 gig HDs
Pioneer Slot loading DVD-ROm 16X
Liteon 52x CDR 24x CDRW 52x Read CD-Rom
ATI Radeon 9700Pro 128 megs ram (Catalyst 3.2 driver)
SB Audigy 2 Platinum Sound Card
Win XP Pro Sp1 (NTFS Format)

3rd Machine Specs: (No Probs) (Muti-Use Graphics Machine)
Dual Xeon 2.8Ghz
4 Gigs ECC DDR 3500 Ram (4 1 gig sticks)
Supermicro X5DAE Motherboard
3 200 Gig WD SE HD's
Pioneer Slot loading DVD-ROm 16X
Sony DVDRW Drive 4x DVD-R 2x DVD-RW 4x DVD+R 2.4x DVD+RW 24x CDR 10x CDRW 8x DVD-Rom Read 32x CD-Rom Read
SB Audigy 2 Platinum EX Sound Card
PNY Nvidia Geforce FX 5800 Ultra 128 megs ram Det.(43.51 driver)
HP Scanjet 4100c USB Scanner
Olympus P-400 USB(Continuous-Tone Dye Sublimation Printer)
Wacom Intuos USB 6x8 Tablet
1 40 Gig USB2 HD, 1 10 Gig USB2 HD & 1 200 Gig Firewire HD
Firewire webcam and Camcorder.
WinXP Pro SP1 (NTFS Format)

I have built and setup/installed all hardware/software for these machines also using the Gigabit ethernet cards in these machines networked to 4 other older( embassed to mention) Machines. I'm probably leaving out some junk on my Dual xeon machine believe me I have a ton of junk connected to it.