Cubase, loops, and desperation

[JoE Silva <theqrm@home.com>]

All-

Just started using Cubase (3.7). Need help with understanding sample
loops and "parts" in the audio editor. Why when importing a perfect
sample loop from a CD or from my audio editor (Sound Forge 4.5), can I
not get Cubase to loop the audio file perfectly just by butting copies
of the original against one another. There is always an audio pause as
Cubase moves from one copy to the next. Sanity is slipping away. Any
help would be a Godsend...