If you already have Amiga Explorer and a null-modem cable, you can't be too far from getting it to work. It really is a good solution.
How far have you gotten? Did you use the setup feature to send the AE client to the amiga? Did that part work?
Have you set the packet size to 512 and set the baud rate low? 9600?
Also, what version of Windows are you using? XP works well with AE.
Maybe describe the problems you are having with AE.