hate to break it to you, but only donators can enter in raffles
Only if the raffle is set to Donator only.
As for the sign in problem, could be a number of things. Did you try the standard "clear out your cache/cookies/other fun stuff"? Or perhaps steam could be trying to detect you are using a new device or something, check your email in that case. More information may also be helpful, such as when you press login does it keep you on steam, or bring you back to the Saxton Hell site? Stuff like that could help.
Also the current raffle just ended so