it will be very slow if
a) the filter cannot be processed on the server side. ie if the filter cannot be processed in the SQL engine then the whole data table has to be sent to you (it's not even limited by range.) the program then applies the range, and filter, to sort out the records. So number one thing to check is that the browse filter is ok. Easiest way to check is to remove it. If the browse then goes fast then put it back slowly.
hint: clarion browses let you BIND stuff into the filter - this makes it client-side.
OR
b) the sort order you have now specified does not match a key in the server. Make it go faster by adding an appropriate key to the table.
cheers
Bruce