> To perform the “Branch if 0” part of the operation, we would like to guide this monstar into the appropriate Branch gadget. To do this, build a room t

> To perform the “Branch if 0” part of the operation, we would like to guide this monstar into the appropriate Branch gadget. To do this, build a room that catches all monstars leaving the counter. This room should consist of a flat floor for the monstar to walk back and forth across, along with many platforms forming trap doors in the floor. Next, force Tim through a second Lever Pull Gadget, whose lever opens one of these trap doors. Build a path below this trap door, leading the monstar to the appropriate Branch gadget. Alright, M1 the first memory "thing", the counter where the result of ADD is stored. M2 is the second memory "thing", the room mentioned in the part quoted. However, you have made me feel rather silly for not realising the very obvious solution to the problem. Thanks.