Well, to be honest, I think the errors pop up out of combat as well, tho not sure. I just turned off the new loss of control option cause I read somewhere it could cause errors. Might be all is well with it turned on but didn't want to risk it during a raid.
This is what's in the !!buggrabber.lua;
["message"] = "nUI-5.07.27 (Plus)\\Bars\\nUI_Button.lua:1004: attempt to compare number with string",
["time"] = "2012/11/28 19:47:05",
["locals"] = "self = nUI_BottomRightBar_Button4 {\n 0 = <userdata>\n feedback_action = 112\n action = 112\n bindAction = <func> @nUI\\Bars\\nUI_ButtonBar.lua:730\n flashing = 0\n rangeTimer = 0.12199999839067\n eventsRegistered = true\n FlyoutBorder = nUI_BottomRightBar_Button4FlyoutBorder {}\n FlyoutBorderShadow = nUI_BottomRightBar_Button4FlyoutBorderShadow {}\n flashtime = 0\n FlyoutArrow = nUI_BottomRightBar_Button4FlyoutArrow {}\n icon = nUI_BottomRightBar_Button4Icon {}\n cooldown = nUI_BottomRightBar_Button4Cooldown {}\n}\nelapsed = 0.028000000864267\ndo_action_update = false\nvisible = true\noverlay = nUI_BottomRightBar_Button4_ActionOverlay {\n 0 = <userdata>\n Timers = <table> {}\n action = 112\n updateHotkeys = <func> @nUI\\Bars\\nUI_Button.lua:703\n nUI_CachedSetAllPoints = <func> =[C]:-1\n abCooldown = <func> @nUI\\Bars\\nUI_Button.lua:673\n cdc_duration = 1.333\n updateCooldown = <func> @nUI\\Bars\\nUI_Button.lua:956\n cdc_start = 1429.981\n button = nUI_BottomRightBar_Button4 {}\n onUpdate = <func> @nUI\\Bars\\nUI_Button.lua:884\n is_oor = false\n b = 1\n r = 1\n actionID = 4\n actionType = \"nUI_BOTTOMRIGHTBAR\"\n is_oom = false\n elapsed = 0\n layers = <table> {}\n nUI_CachedClearAllPoints = <func> =[C]:-1\n nUI_CachedSetPoint = <func> =[C]:-1\n is_usable = true\n updateUsable = <func> @nUI\\Bars\\nUI_Button.lua:764\n is_cdc = false\n nUI_init = true\n}\nbtn_name = \"nUI_BottomRightBar_Button4\"\nbutton = nUI_BottomRightBar_Button4 {\n 0 = <userdata>\n feedback_action = 112\n action = 112\n bindAction = <func> @nUI\\Bars\\nUI_ButtonBar.lua:730\n flashing = 0\n rangeTimer = 0.12199999839067\n eventsRegistered = true\n FlyoutBorder = nUI_BottomRightBar_Button4FlyoutBorder {}\n FlyoutBorderShadow = nUI_BottomRightBar_Button4FlyoutBorderShadow {}\n flashtime = 0\n FlyoutArrow = nUI_BottomRightBar_Button4FlyoutArrow {}\n icon = nUI_BottomRightBar_Button4Icon {}\n cooldown = nUI_BottomRightBar_Button4Cooldown {}\n}\n",
["stack"] = "nUI-5.07.27 (Plus)\\Bars\\nUI_Button.lua:1004: in function \"updateCooldown\"\nnUI-5.07.27 (Plus)\\Bars\\nUI_Button.lua:941: in function \"onUpdate\"\nnUI-5.07.27 (Plus)\\Bars\\nUI_Button.lua:373: in function <nUI\\Bars\\nUI_Button.lua:368>\n<in C code>\n<string>:\"*:OnUpdate\":1: in function <string>:\"*:OnUpdate\":1",
["session"] = 377,
["counter"] = 87,
}, -- [126]
As a side note, the look of the action bar buttons when you lose control of your char seems different as well, far more obvious now that you cant cast. (Unless I never noticed it was like that before offcourse)