You might have seen a 'Bad Jump Destination' error on the block explorer when tracking your transaction:
This is due to a 'biginteger' issue when performing a Max Send. Please try rounding down your amount to one decimal point and typing it in manually. The numerous decimal points is causing a calculation error which is causing a "Bad Jump Destination".
E.g. If you have a balance of 25.432101234, try sending 25.4 instead of putting all the decimals in.
We are working on resolving this issue and will have a fix for this soon!
If this does not work for you, let us know by sending us a support request.