The "v1.1" iteration specifically addressed early bugs found in initial releases. Early item modifiers were prone to crashing the game if the user tried to spawn an item into a slot the game hadn't initialized yet. Version 1.1 stabilized the memory injection process, allowing for a smoother, crash-free experience when modifying the Attache Case.
(often version 5.5 for this era) and inputting that address into the tool to activate it. Availability and Modern Alternatives resident evil 4 ultimate item modifier v1 1 link