First of all, I am a big advocate of Transfer, it is totally awesome and TQL totally rocks. I came up today to almost pulling my hair out on a very simple TQL query and thought I should share this so people have a grasp on details.

When using a query with the IN modifier and a list, you cannot just map a parameter with a value, you have to specify that its a list. (Reading the docs might help!!). Adventurous Luis, went ahead without fully reading Mr. Mandel's excellent docs and of course, fell in a cavernous pit of despair.

Here is my sample: