Is this the lounge located a flight down from departure level?

I'm yet to find a meaningful floor plan of BOM T2 but it depends on what you mean by 'departure level'. There are actually two lounges, one on level 4 (the lounge I visited) and the Business Lounge on level 3. I believe the latter is accessed via elevators to the left of the reception counter. The entrance to the lounge which is next to Costa Coffee was easy to find from check-in/security so you can say it's on the departure level. It wasn't easy to find from transfer security as there aren't many directional signs. I saw a couple of departure gates on this level (level 4) but the majority of gates (including the one used by LH) appear to be on the level below.

Yes certainly a mishmash type terminal.
Anyway the lounge I visited was packed and more crowded then any coffee shop in the main area.

When was your visit?

The whole floor plan is too large to post here but I'm pretty certain the lounge is where I marked with a green arrow on this partial view of the map of level 4.

http://i.imgur.com/mgaOri6.png

I don't know what is on the other side (righthand side on the plan) of the terminal but it looks like another lounge.

On my second visit when I eventually got away from transfer desks (where dozens of passengers were waiting - a bad sign) and transfer security and went up one level the first lounge entrance I saw was the Pranaam Lounge. I went in and was told that as a First Class passenger I should go to the Clipper Lounge. I had no idea where it was and had to ask an airport employee who led me to the familiar entrance of the GVK Lounge. I don't know whether they are still using the old names of the lounges.

The photos I posted were taken late afternoon when the lounge was practically empty. My second visit was around 2am when the lounge was a lot busier but nothing like what you describe.

Was a Europe return flight , so late night ,few weeks ago.

Looks like if you are LH SEN, then you get access to the Premium GVK Lounge in Mumbai which is on level 4. This was not the case in December. Is this something new?

Actually, found out that LH SEN do not have access to the GVK lounge if travelling in economy. I confirmed this 2 weeks back. The LH website says you have access if you hold SEN card, which is incorrect.

Mumbai Airport Lounge

GVK premier access
 

I travelled last week from Mumbai to Zurich on LX in C and was allowed access to the premier side of the GVK lounge. Interior, food and drink offerings were excellent, there was also a restaurant in the back but I assume it is only for First Class passengers as there was a host standing. As an additional bonus every lounge guest receives a complimentary 15 min foot massage which can be topped up in 15 min increments against pay. Internet connection was fast and reliable and the showers were clean and spacious. Definitely one of the best lounges out there, the new Mumbai airport is also stunning, next time I will definitely accept the waiting golf cart on arrival as the walk to immigration took approximately 15 mins.

Hmm, the LH product manager responsible for Lounge service confirmed to me that M&M SEN and SAG(*G) travelling in Y have access to the GVK Business (not Premier) lounge section.

Great ! Thanks for the update. I'm also clarifying this with LH.

Do you know whether they will honor the SEN +1 guest & kids policy too? Travelling with the family on AI in economy & wondering if I can use the GVK lounge.

Its upto AI for that. AI will issue you lounge passes for LH*G +1, but not for kids. In my case when I asked what to do with my kids in CCU, the AI checkin agent smiled and said 'kids don't count' when I asked 'what?' she smiled and said 'not for star alliance, but also not for the contract lounge'. And indeed at the TfS contract lounge they didn't say anything about the fact that we had the two boys (5&7) with us. They just collected the two lounge passes and let us in. Maybe the same applies in BOM for GVK.

Did not work for me this Saturday. AI agent handed me with 2 passes - one for me and one for my wife but not for my kids (6&9). Talked to AI supervisor - said, he had instructions not to give more than 2 passes. When asked - how do they expect me & my wife to enter the lounge w/o kids - why then even give lounge passes to families (2 A+ children). He blamed it on GVK lounge.

So went to the lounge, access to kids was denied. Called the manager, spoke to her - she said she can only allow the adults and not kids - when asked, what should the kids do? She said - don't know. Then, she said, she can allow only 1 kid. It was getting more and more ridiculous now - sorry to say but it was like begging for them to allow a 6 year old to a lounge. Finally, convinced her to allow wife and kids in the lounge. I went to the loyalty lounge as I had priority pass.

I have sent feedback to AI & possibly sending one to *A. I know won't help much but thought I will try. AI agent said that they have had lot of complaints already. So I would request you all to submit your feedback on AI website -

http://airindia.in/feedback-form.htm

I'm reaching BOM way to early at 7:30 PM before I board the LH 757 to FRA at 2:55 AM. I have booked a 4 hour stay at the new airport transit hotel, Niranta but wondering whether I should head to the Mumbai GVK lounge instead. But that will require me to check-in.

LH 757 departs at 2:55 AM, which means they will open for check-in at around 12:00 midnight. There is a LH flight to Munich that departs at 1:00 AM for which check-in starts at around 10:00 PM.

Does anyone know whether LH agents will check me in early for the LH 757 flight? I don't quite remember but I think they have done that in the past when I showed up at 10:30 PM, almost 4+ hours before departure.

If the desk is open, they will check you in.

Yup, they will!