Wirelessly posted (htc Pocket PC: Mozilla/4.0 (compatible; MSIE 6.0; Windows CE; IEMobile 7.11) Sprint MP6950SP)
I don't play many 3d games on mine but I would say install to card if you can.
I use the HTCWiFiRouter app that is integrated into CommManager. It is available in the WinMo Software Forum. ICS for wifirouter is Internet Connection Sharing using the WiFi connection as a link between your device and pc.
I have never seen that commit registry or flush.
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There are apps that will optimize or clear unnecessary values and keys from the registry like sktools but I haven't seen that commit or flush as part of the standard settings.