Cust/Vendor fors on application between LCY and FX missing

Hi all,

I have searched through the forums and not found an exact fit for my issues here.

Currently the following scenario happen in a 4.02 environment.

The client has EUR as LCY, they have a purchase invoice in CHF swiss franc then a payment is applied in LCY from payment journal with the currency column set to blank as it is LCY.
The exchange rate columns have the following relationship CHF to USD as the US is the headquaters so the issue is partly to do with this relational currency setup.

When the LCY line is applied either in a payment journal or from the vend ledger entries the following happens. The payment is set to applying entry the Currency fields in the top of form 233 and the balancing lines are set to blank. In this scenario the APPl Remain amount is then based off a CHF to USD exchange rate. It would seem the code cannot handle the blank currency field and recognize it as LCY. I have shown this by manually inserting a EUR into detailed and vendor lendor entry for the application this works to resolve the issue but is a manual action on the line. Even if i add EUR to a payment journal line during posting the EUR is set to blank as it is LCY.

I have shown this is a failing in CRONUS as well as our environment,

My thoughts were to make the application code recognize the Blank and insert the EUR (LCY) into the application,

I was after others experiance or suggestions