My Game Builder will be down for maintenance on Saturday 21st from approx 9am Pacific Standard Time. Forums will be up, but the MGB editor/player will be unavailable.
We are moving the main account server to the new machine to reduce costs, tighten site security and improve login performance.
We estimate that My Game Builder should be back up by around 4pm PST if all goes well.
[EDIT: Back up .. at 4pm! just made it... Check you have build 186 in your browser, report any new issues in this topic.]