When using Singapore's Immigration & Checkpoints Authority's Submission of Application for Visa Electronically system, I had a funny problem. After configuring Internet Explorer as instructed, on the page that says "Welcome to SAVE This facility allows you to submit a visa application online through your local contact.", after clicking on "Proceed to Submit", it briefly says "redirecting to SingPass" before stopping on a blank page.
I found this post: Strange problem of Singapore ICA’s SAVE system that said the problem was adding things to the trusted sites. I removed the psi and enets sites and it still didn't work. I removed, I think, singpass services and it works! So if you're facing the same problem, try it. Not sure how it affects the rest of the application, though.
Oh, and it looks like you have to apply 30 days or nearer to your intended arrival date. Processing time is supposed to be one working day, and they seem to give a visa starting from the approval date, so you can arrive earlier than you intend to.