One of the issues I sometimes have is that the Checkpoint VPN Client Tray Icon (the yellow key) sometimes disappears from my windows xp start bar. If I try to re-run checkpoint it says its already started. I just found out how to get it back without restarting my laptop - kill the SR_GUI.exe process. Things will automatically restart and the tray icon re-appears again.
BTW...I hate Checkpoint VPN...compared to Cisco VPN its an unstable horrific piece of software. I guess you get what you pay for.