Loosen the Nexus bellcrank fixing screw with either a 10mm wrench or 5mm allen key, then slide it off the axle.
The unit pulls off the axle nut towards the right side of the bike. (left in the photo above)
Set aside the shift pin that sits inside the hollow axle.
Version 2 of the Compass has different hardware than the previous versions. The instructions below still hold true but the hardware in question is different (uses different tools). See the image below for the circled hardware. The large 4 main bolts were updated to cap head bolts that use an 8mm allen key with a nut on the backside. On top of the 4 large bolts are two smaller ones just under the basket that use a 5mm allen key with a nut on the backside.
Loosen the axle nuts (15mm) on the internal gear hub, both left and right. Loosen the axle carrier bolts (8mm allen for bolt and 17mm for nut). It helps to have a narrow, compact wrench like an open-ended or box wrench to access the bolt head on the inside between the disc rotor and the frame.
Pull the internally geared Nexus hub backward in the slotted dropouts of the frame until the tension on the primary chain is tight. You should be able to move the chain up and down about a half inch in the middle.
Tighten the drive-side (right side when upright) axle nut first, then tighten down the non-drive side (left) axle nut of the internally geared hub. Check primary chain tension by rotating the chain to see if there are any spots that are too tight.
*Some bikes will have a silver chain tensioner attached under the drive-side axle nut of the Nexus hub. This piece is installed at the factory to keep the chain in place before the rear end of the trike is attached. If you cannot get the primary chain tension set correctly because of this part, feel free to remove it. It is not required and has no effect on function once everything is tightened properly.
Tension the secondary chain by pulling the whole axle carrier backward. Tighten one bolt and check the chain tension by rotating the left wheel and looking for tight spots. Due to the many connection points, there is a chance that there will be a tight spot and a loose spot of the secondary chain. This will remedy itself during the break-in period. Use the tightest point in the secondary chain as the baseline for this tension adjustment, meaning the chain should not be overly tight in this position. Due to the shorter span, look for a 1/4" of movement in the middle of the chain.
*Some bikes will require more rearward movement than is allowed by the small, upper bolts. Much like the chain tensioner on the Nexus hub, these mounts are present to ease assembly and are not necessary for the bike to function. If you need to slide the rear end further than these mounts will allow, just don't use them.
Tighten all hardware. Reinstall the shifting components in reverse order of removal. Make sure the shift pin is installed in the hollow axle before reinstalling the shift mechanism. Slide the bellcrank onto the axle until it stops, then tighten the fixing bolt.