Wow, Jimjams, great pictures. I had only seen the top one. He does have your cheeks!
My youngest was two at the end of September. It should be very easy to get his hearing tested here. I have "Baby Talk" that you recommended and I've used some of that. All of my nieces and nephews have had ST for one reason or another (autism, super preemie, CP and general "why not" ) so I can get info from my SIL and sister. SIL does ABA also with her son (5 yo) and I might ask her about some of those techniques. I really don't think there's any serious underlying reason for his late development; it's probably a combination of little things that have added up. Not to say I don't get worried, though.
Davros, thanks for the links. Yep, we're in CH. I'm not doing a sensory room, but a safe room for my active boy to relieve some pent up energy. It's been strongly suggested that I do this for some problems he's been having and, also, because of the problems his problems are causing me. Anyway, looking for a ball pool, I came across some insanely expensive websites dealing with SN and sensory rooms. I nosed around them and found cool things that I thought my son would like, then searched here looking for cheap ways to do them.
The thing with the lights is mainly because I like lights and it sounds like a fun project for me. The room will be in what is now our bedroom. I'm hoping we can take down a wardrobe and use that space for a hanging chair (from IKEA here ), a lava lamp, some moon shaped lights I have and surround it or make the "entrance" a curtain of lights. Quite honestly, it'll take us a couple of months to do everything and I'm sure that everything I'd like to do won't get done. But hopefully enough for it to work for us.
SueW sent me a link a while ago to the IKEA site and I've ordered loads from there -- they have very cheap active play toys. At least I think I've ordered it. Got an email confirmation but no delivery date... and it says "payment on delivery", so I've got to stash some money somewhere to pay the guy when/if he comes. (Thanks SueW!)