We are based in Queen Mary University of London's Mile End Campus [pdf map]. This is 20 minutes on a bicycle to Tower Bridge or Angel; 15 minutes walking to Victoria Park. Our contact information:
We are on the 5th floor of the recently-refurbished Fogg building
(yes, its green; left: view from East; right: view from Bancroft road).
Citymapper and Google Maps work very well for the London public transport system (including for cycling).
Once your here:
In the Fogg building, take the elevator up to 1st floor reception and they will come get us.