If you mean that you want to import a completed song or loop pattern that was created in Acid then do the following
From Acid just select file, render as and select a file name and location to save it as a stereo wav file.
In Cubase start a new project, set it to the same tempo as the acid mixdown then on a new audio track select file, import audio and select the wav file to import.
If you mean that you want to use Acid loops within Cubase to create a song, then I'm not sure you can do that with the version of Cubase that is packaged with the Tascam. Only Cubase SX 3 is capable of doing that.
Hope that helps.