I am currently using GRETTAcuriosity, GRETTAemoticon, GRETTAlonely, and GRETTAmusicidle.
All of these are minute timer plugins. They are all running at the same time.
Now with that said, lonliness 2.3 might not be compatible. (haven't looked into it)
GRETTAlonely is very similar, and you might try that one. It is compatible with the others you are using. I highly recommend doing this before you try the other steps I am about to give you. You can always change the things that Hal says while idle by editing the plugin file. It's pretty easy.
I have had multiple issues with the CDbl function in UltraHal. It can be caused by a multitude of things. You might try: First making sure you have the latest version of the GRETTAcuriosity plugin, and all other GRETTA plugins you are using...very important. Second open Hal and go to the Brain options, MAKE SURE THE BRAIN YOU WANT TO USE IS HIGHLIGHTED, and pick the options you want for the GRETTAcuriosity plugin and click "apply" (i know you have already done this, but please try these steps). Third close hal, and restart Hal. Go to the brain options and make sure the brain you are using is highlighted (if not, highlight it and click "apply").
Then try it. If it doesn't work then close Hal and open the brain editor. make sure that it is putting a number in the "PERSIST" field in the "curiosparameter" table. I don't know why it wouldn't have a number there, but it would help me figure out why you are having a problem. It might be an incompatibility issue with "lonliness 2.3" or one of thos wierd Hal database quirks. Sometimes Hal has issues with the database connection when different options or plugins are activated and Hal is not restarted. If you ever get an error then I suggest you close Hal, and restart it.
Let me know what happens - the dude