It is not possible to go back to the old schedule due to the database differences/changes. Have you seen the thread where the old schedule is approximated?

http://www.managerforum.net/viewtopic.php?f=233&t=12496

Or the tools available to create any number of unique configurations?

http://www ...

We have been using it for several months, we are very unhappy with how time consuming and cumbersome it is.

Please specify what part of the process we can help with. It's quite possible we can solve it with some specific attention.
I am not sure where to start - we get a lot of walk in business ...

We have been using it for several months, we are very unhappy with how time consuming and cumbersome it is.

Why do estimates appear on the scheduler?