No problem, man. I would also assign the “generic” expression to the xylophone, and make the initial dynamic of that instrument p or even pp, so the user can really hear the difference as the crescendo plays.
Your G2 tom is still set to the “Tom-tom (Low)” instrument, too, in your percussion map. It should be the “Tom-tom (High)” instrument.
Your work here is superb; this is THE standard for Spitfire percussion set-ups, as far as I’m concerned. I love your choice of music for the tubular bells, very appropriate. 
Apparently, Dorico actually doesn’t handle unpitched percussion cresc./dim. prooperly (according to Daniel Spreadbury himself). I guess Spitfire just allows us to fake it using the CC11 expression controller. 