Did you get an answer to your problem?
I have had problems loading the sybase module.
I too am using SQL Anywhere Studio.
There is a dll dependency problem when I try to load the php_sybase_ct.dll.
It is looking for libct.dll which I believe is a Sybase dll.
My concern is that the php module is only designed to access the larger Sybase server products like version 11 and that SQL Anywhere ( currently using 7.02) is NOT supported.