+ How can I find out about the nearest and next GBC exhibition?

Find events using one of these calendars then ask the event sponsor if they will be having a GBC.

+ How do I add my module to a GBC exhibit?

Some events are open, especially at AFOL conventions, but most exhibitions are by invitation. If you are an event participant, seek out the GBC coordinator. Each coordinator will have his/her own rules about participation, but these tips will improve your odds.

Follow the standard. If your module follows the standard, it will be easy to integrate into the collaboration. If it does not, it will be a pain, and the GBC coordinator will remember you for it. Demonstrate success. Share a video of your GBC working consistently at the standard rate of one ball per second. Volunteer to help during public hours. Helping run a GBC is one of the best ways to learn about GBCs. Be at setup when you said you would. The coordinator has to know everything will work at showtime. Stick around until your module proves itself.

+ Can I bring a copy of what others have done in the past, or does it have to be original?

Reliability is far more important than originality. Often multiple copies of a module look just as good, or better than, a single module. Besides, coming up with something original isn't trivial, and coming up with something original and reliable is doubly hard. Ultimately, of course, it's up to the GBC coordinator.

+ My module is made from parts in my collection, so nothing is color coordinated. Does that matter?

Reliability is more important than beauty. But the best GBC modules tend to have a definite color scheme or theme and a certain elegance. Again, check with your coordinator.

+ We are just using battery packs to power the modules, but looking at videos I see some type of controller that must plug in to AC power. What is that and do I need one? Where do I get it?

These are train regulators from the old 9V train system. For a collaboration, check with the coordinator to see if she expects you to bring your own. However you might want one for yourself as it has a built-in potentiometer giving six forward and six reverse voltage outputs for controlling speed. You can get them from BrickLink or other sellers. As of 2015 they were about 12 USD from European sellers and a bit more in the States. You will also need a 1 amp, 9-12V (VAC or VDC, either one) AC adapter for your country. You can use a LEGO branded power supply, but availability is limited. If you don't mind using a non-LEGO power supply, you can get them inexpensively wherever used electronics are sold. If you are using Power Functions motors, you will also need a 8886 or 8871 Power Functions extension wire, as the light gray end connecter doubles as a converter between the old 9V system and Power Functions.

+ We are using 8882 Power Functions XL-Motors and 8883 M-Motor motors. Any issue with using these? One better than another?

Nothing is wrong with either one. The M-Motor is the cheapest LEGO motor available and usually powerful enough for a GBC module, so they are commonly used. The XL-Motor is readily available and is useful when you need more power.