Version 1.5 has been replaced with HG 2.0 as of this writing though a number of HG enabled grids are still using it. There were 2 versions, HG 1.5 and HG 1.5 i7 which were not compatible with each other and jumps between them will either partially or completely fail.
This version has increased security by limiting the hyperjumper's inventory exposure to other grids/standalones to what is in the My Suitcase folder which sits outside of the My Inventory folder. Inventory items picked up on hypergrid travels go into the My Suitcase folder and once back on the travellers home grid the item(s) are moved/copied from the Suitcase to the appropriate My Inventory folder. In practice the move/copy did not always work well except with web frontends ie Diva's Wifi, that were specifically coded to allow the transfers.