JoinFieldValue in workflow

 Hi,

I have a scenario where I have to stop user from saving a record from a certain sales stage and onwards if the Customer Account Type is of partner. I have written this expression but its not working for some reason, it triggers at every stage....trigger event is "Befor Modified record saved".

Can somebody validate if this expression is right,

([<IndexedPick0>] <> LookupValue("OCC_INDEX_CUST_LOV_OPTY_0", "ABC") OR [<IndexedPick0>] IS NULL) OR ([<IndexedPick0>] = LookupValue("OCC_INDEX_CUST_LOV_OPTY_0", "ABC") AND (PRE('<SalesStage>') <> 'Qualification' AND PRE('<SalesStage>') <> 'Development' AND PRE('<SalesStage>') <> 'Confirmed' AND PRE('<SalesStage>') AND 'Bid/Proposal Preparation' AND PRE('<SalesStage>') <> 'Decision Pending')) AND (JoinFieldValue('<Account>',[<IndexedShortText1>],'<AccountType>') = 'Partner')