WINPILOT WOES

All,
I'm fairly new to using an Ipaq and Winpilot Pro (connected to a
Cambridge 302/303 for GPS input) as my flight computer. My previous
experience was with an SN-10. The more I fly with this combination the
less satisfied I become. On the ground and in simulator mode
everything seems to work fine. But in the air, especially after I have
been flying for a few hours Winpilot seems to bog down. It appears as
if it is being overloaded with data, or is being overwhelmed in some
fashion because it sometimes takes almost a minute after thermalling to
realize I'm in straight flight again and update the moving map. In
addition, if I try changing the Macready setting after flying for a
while, I have to pause at least 5 seconds between taps on the screen
for it to "repaint" with the new value. On my longest flight with this
setup it actually blanked out entirely and I had to do a hard reset in
the air to get it back on line.
The handheld is an Ipaq 3835, and if I remember correctly I installed
an additional 16M of memory in it's expansion slot.
Does anyone with more experience with this (common) computer/software
setup have some advice that might help me out? I'm hoping I simply
just have a setting wrong somewhere.
Respectfully,