I discovered this with an animal companion. When both the master and AC are open at the same time, right click on an equipment item in master and select move to (companion). PCgen displays "insufficient funds" error message unless the companions buy mode or gold total would allows the companion to 'buy' the item. I think this is wrong. Moving (or copying) an item between characters (or companions) is not a buy/sell transaction.
However, when the "insufficient funds" error message appears, the item is removed from the master and never appears on the companion. Even if this is supposed to be implemented as buy/sell events, the item should not be removed from the master if it did not successfully transfer into the companion.
Secondly, in any case where an item is moved between the master and companion (regardless of whether there was an error in transferring the item), if you immediately check the destination characters equipment tab all items shown in the equipment list on the right have blank names and many of the items in the purchase list on the left also have blank names! The names remain blank until the user selects the master's equipment list again and then goes back to the companion's equipment list. Sometimes you have to switch back and forth between the master and companion two or three times before the UI shows correctly.
I've confirmed that this error also exists in the 6.5.0 snapshot from today.