strange errors during sell orders with metatrader api

 
hello,

here is the order i send on my mini forex demo account :

type=OP_SELL lots=0.1 symbol=USDJPY for example price=current bid
stop loss=0
take profit=current+50pips for example

i have very often an error message "invalid S/L or T/P", sometimes "unknown error", sometimes "some error" (when i'm in debug mode) and some times "time out"

i've successfully sent the same order for AUDUSD for example (even if sometimes i obtain the same invalid S/L or T/P message ).

what are the exact rules for selling ? on forex there should be no "sell on up tick" rule ...
is it a bug/limitation of the api (i use the version 3.72) ?

what is the last mtapi.dll available for the version 3.xx ?
 
sorry i've made a mistake in the above text, of course when i sell the T/P is less than the current price (T/P=current-50pips)