>>I am running FP 2.5 and have been inactive for too long to remember some basic skills.
>>
>>1) How do I look at an existing cdr index to see what it is indexed on and make changes to it?
>Sorry folks, I mean existing CDX index not cdr index.

Go to the menu Window -> View or type SET in the command window. Use 'Open' button to open required table. After that click on 'Setup' button to view/modify table structure and indexes.

>>2) I use a validation clause for a variable used during a get. It looks up the value of the get variable in a table to see if it already exists. How can I change the value of the variable before I send it back to the calling procedure? Currently I send back a true of false, but I need to change the value of the variable depending on the results of the lookup.

It's hard to tell w/o seeng your code. If you're doing validation directly in Valid clause than you can change variable directly and use SHOW GET to refresh it.