Stock Locators- advice for use of non-std code

Hi Community

Please check attached file for details.

We use Stock locators in almost all the organizations. Therefore in many forms, there is a need to use Stock Locator window to fill locator in transaction line. When a user is registering a New line for example in 'Subinventory transfer' so after choosing 'Item' og 'Subinventory' next field is 'Locator'- to choose locator comes a 'Stock locator' window which is always having the same Subinventory chosen (in our case 'HL' main Warehouse). We would like to have there same Subinventory as it was just chosen in previous field under registering new line in Subinventory Transaction form.