Personally, having equipment that will allow a physical shift in C.G. without the ability to account for it
not to worry .. any half competent design (wo)man can sort that out for you .. providing that the structural bits are OK, the loading stuff is just a matter of tweaking the loading system to suit the need.
the stretcher itself has no weight limitation
most unlikely .. keep in mind that the design structure has to address the crash loads in the design standard (for the AS350
FAR 27.561 will be the first stop to look - as always, this is the current static rule and may not apply explicitly to the 350).
although with operational and paperwork issues
simpler than you might think .. but probably/possibly not warranted if you ran a population CG distribution exercise
How you get around the loading system implications is a matter for the local regulatory jurisdiction but, from an engineering viewpoint, will be pretty trivial
For the lb/kg problem .. a Mk I eyeball of the patient on arrival will resolve that question
Just as with the pilot's station at 61.02", one has no way of legally adjusting for full forward or full aft location
while I can't comment on the specifics in a particular jurisdiction, this comment probably is not correct ... the loading system needs to address the regulatory requirements and, generally, can operate within the intent of the FMS even if there be minor variations for a specific application .. hence
unless you have something else officially blessed
Useful to keep in mind that there is no basis for calculating loading to the gram and millimetre ... the empty weight and other data doesn't support such accuracy.