While an improvement in some ways over the previous (now defunct) incarnation of the Royal Institute Dictionary online, the newly-released RID 1999 online for now may have to remain in the "not ready for primetime" category.
I noticed a while back that it was missing large chunks of two letters of the alphabet: ต and ส.
ต Complete up through the entry ตา ๒. That means entries from ตาก to ไต้หวัน are missing. If you compare it to the paper version, that's 28 pages of the dictionary, or roughly 400 entries gone (one entry may include several or even dozens of subentries).
ส This one ends at สาด ๒. So we're missing from สาต to ไสว, a whopping 64 pages, or upwards of 1000 missing entries.
So what gives? I emailed the Royal Institute about this over a month ago, and no word yet. In fact, since I first noticed it, now the letter ต doesn't work at all (any word beginning with ต will return no results, and you can't browse the letter, either), while that large chunk of ส is still AWOL. Let's hope this means an update is on the way.