We used GB for a year with BiaB before switching to Logic Pro. Whatever tempo you set in BiaB to generate the tracks should be what they retain when drug or imported into GB. I would not try to modify the tempo in GB unless you really know your way around it. It's easy in GB and LPX to accidentally nudge a track or worse to accidentally stretch or shorten it when attempting to do something else. To change the volume you use "automation lanes" where you can raise or lower the gain on a track anywhere you desire and shape the gain to come in gently and leave the same way.

Here's a screen shot of one of our projects showing extensive use of the volume automation lane: https://www.janiceandbud.com/uploads/4/4/3/1/44312/al_orig.jpg

Regarding the tune Robert well captured our feelings:

"Catchy and sung with feeling. Its a well written song and your production is impressive for early in your BiaB journey.
Background vocals work well. You`d probably get more detailed answers to your tech. questions by posting them in the Recording forum.
Look forward to hearing more of your songs."

Best to you on the BiaB/DAW journey. You will reap rewards from the initial frustrations, etc.

Enjoyed it!

J&B

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