What struck me when I first heard this piece was how filmic it seemed.
There was a BBC (?) miniseries shown in Australia a year or two ago: Vanity Fair (after the novel by Thackeray). Unusually for a costume drama, the music was along the lines of bent-classical-meets-brass-band ... all sorts of "wrong notes" and looseness in the playing ... and to me (fwiw) it worked a treat! Your piece made me think of a not-dissimilar take on a fairground or 1950's seaside resort. Possibly faded and seedy and oddball. Maybe about someone getting lost in a mirror maze, where everything is distorted and surreal. Instead of a "nice" trio of violin, cello and piano (say), you've used three "less-nice" instruments: sax, euphonium and accordion. (I can see those flames heading my way...!!)
Daydreaming further ... I thought that this piece might present (and gain marks) more effectively if it were part of a submission relating to film – even if it were to be presented in conjunction with a storyboard or whatever ... ergo: a viva voce might work in your favour over just leaving the work "uninterpreted" at the front desk or wherever.
Back to the nitty gritty – there seem to be notational issues which might be down to the software I'm using to read your score. (Mac X 10.4.11; Sibelius 5 demo – and I'm anything but a power user!) Is this score close to the version you'll be submitting, or just a sketch? (If it's just a sketch, all of the following will be redundant, but here are some points nevertheless...)
• the eupho seems to be notated in concert pitch, 8va, treble clef. For a concert-pitch score, would the eupho be better at sounding pitch, bass clef?
• the whole accidental situation looks a bit iffy. Some passages have a mixture of sharps and flats where either all sharps or all flats might read better. (Eg: opening sax phrase.)
• some accidentals seem to be repeated within given bars for no apparent reason. (Acc bar 26, bar 89, but numerous instances.)
• ditto occasional odd placings of accents and staccato marks.
• is the altissimo register OK by your sax player? OK by the examiner? (...so you don't get marked down for writing above written F or F# or whatever.)
• various quaver and/or semiquaver groupings look a bit sus. Some examiners will be fine about it; others might get stroppy! (Acc LH bars 14 & 16; 17-20; RH bar 41, 87, 88 ...)
None of these factors need be a huge problem – it's just that, if the examiner got out of the wrong side of bed that morning, it could make a difference in the marks you get.
No slaughtering!!

Thanks for posting it – interested to see how it all goes!
jada
[stop press – just saw your posting of a couple of minutes ago:
I haven't as yet tidied up the score – which obviates many of my comments. Hope it all goes well!]