I don't think 1835 questions is too big, but I am no 100% sure.
Hi Tim
One quick question regarding the issue above: Is there a time limit for the question bank to load? perhaps 60 seconds or some other time frame. Just wondering if given the amount of questions, could it be that the request times out or something similar.
PHP applies a time-out to most requests, but that is a server setting. (That is, you can probably change it.)
Try using the browser's developer tool (F12) network tab, to see what is going on as the dialogue opens. If the requests stops after an exact amount of time (e.g. 60 or 120 seconds that is always the same) then it is likely to be a time-out.