Not entirely doom and gloom.....
Section C 1.2 LASORS states....
....
In circumstances where previous flying training
towards an ICAO PPL(A) (non-JAR-FCL) has been
conducted but no licence has been issued, PLD will
consider the crediting of such flight time towards the
issue of a JAR-FCL PPL(A). In all cases, applicants
must apply in writing to PLD enclosing appropriate
training records and flying logbooks for the PPL
training received. PLD will review the training
records to establish a course of training and advise
the applicant accordingly.
...
Anyway, the aeroplane flies the same in the US as it does in the UK. My advice, get the basic general handling and 'flying' the aeroplane (including take-off and landing) done where it's cheap, then finsih the Navigation and cross country over here in the environment that your more likely to fly in.
HTH
DD