For llDialog returns, I have always used something like this for searching multiple lists: if (llListFindList(d_list + c_list, [msg]) != -1){ It will search through both lists "d_list" & "c_list" for a match. In MONO it is taking and appending the c_list to the d_list and then throwing an error: "Object: llDialog: button list too long, must be 12 or fewer entries". Even though d_list contains 7 items & c_list contains 6. list a_list = ["a", "b", "c", "d", "e", "f"]; list b_list = ["integers"]; list c_list = ["1", "2", "3", "4", "5", "6"]; list d_list; key owner; integer chan = -87643; default { touch_start(integer n) { owner = llGetOwner(); d_list = []; d_list += b_list + a_list; llListen(chan,"","",""); llDialog(owner,"test",d_list, chan); } listen(integer channel, string name, key id, string msg) { if (llListFindList(d_list + c_list, [msg]) != -1){ llOwnerSay("@llListFindList; " + (string) d_list);///////////////////////d_list if(msg == "integers"){ llOwnerSay(msg); llDialog(owner, "integers", c_list, chan); } else llOwnerSay(msg); } } } LSL1 returns: Object: @llListFindList; integersabcdef MONO returns: Object: @llListFindList; integersabcdef123456(d_list has had the contents of the c_list appended onto the end) NOTE: This may have been incorrect behaviour all along in LSL1, can not find any documentation that it should have worked that way.