KeeForm works only, if the username and password fields are on the same page.
KeeForm uses just a simple, but effective heuristic method to automate logins, and it works 98% of the time ("ballpark estimate"). For the remaining 2% you can still use KeePass' auto-typing.
Having said that, should you ever encounter a one-page login where KeeForm does not work, please do send us the URL. We will try to improve KeeForm.