Question about Custom Report Options

[Sean McLennan]

Just looking for confirmation of a suspicion I have...

I'm building a custom report and ideally, I would like to have a user 
select a vendor and then allow the user to select a payment from a list 
of payments made to that vendor.  I think this is *not* possible because 
you can't update the options windows based on selections made in the 
options window.  Is that correct?  (Open to thoughts on how to work 
around that if anyone has them!)

I'm also assuming that there is no way to pass a transaction to the 
reporting tool? Say if the user selected the transaction in the register 
first and then opened the report like the check printing works?

Thanks in advance,

Sean