You got that error because in the code you put in you put
if %user.client.bl_id = 159
Where you should have put
if(%obj.client.bl_id==159)
Thanks to MrPickel for picking up the %user problem.
Take note of the double equals means you're checking to an integer, wheras a $= means you're comparing it to a string. Also be aware that it is good practice (I'm not sure if it's required) to use brackets around the condition in the if statement, so where
if %pie $= "yum" {}
would fail,
if(%pie $= "yum") {}
would work.
EDIT:
Also, open the .cs file in an editor which allows you to goto lines or has the line numbers on the side, so you can check lines #311 and #621, as the console reports there are errors on at least those lines. Also, I'm not sure if the reason there is only a single equals and no brackets is the console error formatting's fault or yours, but just check anyway to make sure it's not yours.
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