No, there is no way to directly convert vJass to GUI, mainly because vJass requires the external compiler from JNG to make sense of the code used in it which isn't present in GUI. Also note that using Jass in general allows you to supersede the structures normally used in GUI and allows for some additional functions not present in GUI, thus direct conversion from JASS to GUI is impossible too.
Really you could just go through and using the original system (if you understand it) as a base to make your own with a similar method, but it may just be easier to make your own system if you can't read Jass.