A custom report runs like this because all the data has to come across the network to the work station before Crystal starts to sort and filter the data before displaying the results. If large tables are involved you get this. It runs fast on the server because the data doesn't go anywhere, it is churned right there.   The reports native to Sage are faster because they work off works tables which through programming limit the data to just what is needed.

A common solution is to use Microsoft Access to pull the data and then base the custom report on the Access database. This will speed up the report tremendously 

Standard?  Advanced?  Premium?

And another thing. Linking of tables makes a huge difference.  If you linking is wrong it will slow down the report tremendously.  The table with the most records should always go on the far left. The groupings should be based on fields on the driving table on the far left. 

• Instead of grouping a field within the report, group on a formula instead. This might sound crazy, but grouping on formulas decreases the grouping time. Just add the field you want grouped to a formula and group off the formula instead.

• Turn on Sage 100 Client / Server ODBC. If you are running the Sage 100 Advanced Version, you can turn on the Client / Server ODBC. Most people do not turn this on and it should be turn on for all installations.

• Try using Subreports. Subreports can sometimes speed up reports, but can also make exporting the report a little challenging.