Hello,
Here's an update to this thread.
I applied for an Indian visa in Kathmandu this week, and the procedures have changed.
First, don't even bother trying to fill the online form out by yourself.
EVERYONE who did this had their forms rejected (including me) because of minor technical issues (present address wrong, city names spelt wrong, forgetting to to check a hard-to-find checkbox, or, the gravest sin, adding or changing any information by hand, using a pen.)
The whole place was full of angry, frustrated people clutching useless forms rejected for what any normal person would consider trivial reasons.
Instead, just go to one of the travel agents directly next to the embassy and let them fill out the form for you.
It costs 300 Rupees to do this ($4), and the agents are experts in knowing exactly how to fill the forms out so that the embassy will accept them.
They'll also do all the photocopying for you and photos for cheap if you need them.
If you get to one of the agents by 8am, you'll have your application ready by 9:30am when the visa office opens.
Then it's easy - just take a number from the automated machine, wait a bit, pay the RS4150 fee, and come back about a week later with your passport to get your visa.
By the way, the Kathmandu office does not like giving out 6 month visas.
If you need a 6 month visa, fly to Bangkok in instead - that office is much bigger, professionally run, and understands tourism.
Anyway, you'll love Thailand, it's great!
PS: You don't need a transit visa if your flight out of Nepal connects to another international flight in India.
If you fly through Delhi or Mumbai, you'll just stay in the international terminal, so you won't have to actually enter India.
However, if you have to personally collect your baggage from the luggage belt and re-check it, ask the airline ground staff to do this for you - it's very routine, I've done this twice.
(The only time you need a transit visa is if you have an additional domestic flight, say from Delhi to Mumbai, to catch your flight out.)
UPDATE:
I applied for a 6 month multiple entry visa.
This morning I went to submit my passport and was told I would get a 3 month single entry visa.
I expected this, so it wasn't a problem.
There have been rumours of 6 month tourists visa being granted, but I wasn't able to confirm this or met anyone who received one.
If you were granted a 6 month visa at the Kathmandu embassy, please post here with your experience.