Hi,
When I logged in first time to Bucket Explorer, and I have unchecked the check-box of "Show Tip..." that time, next time on every start of Bucket Explorer it did not prompt on start-up,
now how can I get tip window again?

Hi,
You can get Tips & Tricks window from Help --> Tips & Tricks.
If you wish that this window appear at start-up then remain checked "Show Tip on StartUp" check-box.