CC was worked on in the spare time of volunteers for 4 years, most of us on full-time university courses during that working on Classic on the side. It's hardly comparable to full-time development by a company. Also, we're now a 2-man company already working round the clock, there literally are not enough hours in the day for us to go back to working on Classic, especially when there's no financial benefit to us doing so. In fact, since Classic is so difficult and time consuming to work with, diverting resources away from the profit-making C2 could actually sink us completely at this time, so it's genuinely off the cards. On the other hand it is open source and there are some other developers working on it - r2 is in the works and should be out soon with some minor fixes by other devs.
Again, these problems probably can't ever be fully resolved for technical reasons - Classic really is beyond repair - the bug fix is Construct 2. So yes, it would be super hard work, and certainly too much work for official Scirra devs. We're still supporting the work involved in building and distributing new releases so we are helping to keep it going, but that's as far as it is possible for us to practically help with Classic at the moment.
Finally, I'm afraid to have to put it like this, but I don't think we're obliged to spend long unpaid hours working on some software you got for free, especially when we have already fixed all the issues and called it Construct 2.