I recently saw some occupied Warre hives for the first time and had an opportunity to study them up close. One thing puzzled me – why did the boxes not lock together, perhaps with simple overlapping bits of wood? There seemed to be nothing to stop the boxes sliding around. For example when we tipped this section, the one above began sliding:
Opening Warre, seen from below
Simple Bees 
Once the bees have propolised the boxes together, they are pretty solid. In this case, the quilt box was not as propolised as I thought it was. Hence the slippage. Normally, one would remove the quilt box before tipping the next box as I did here, but this hive was lacking its top cloth and I did not want to expose the bees. Simple projections in the middle of each side of each box would prevent this but I don’t think anyone bothers. Many Warre beekeepers put a load strap over their hives during the winter to aid with stability.
Gareth, West Oxfordshire
When the Warre hive is inhabited by bees, the bees ‘glue’ the gaps between the boxes with propolis. I would imagine the Warre hive you describe has not had bees in it. Personally, I would be in favour of the overlapping bits of wood you describe which would let the bees make a really immovable join. The only reason these have never been part of the hive design is so interfering bee keepers can take apart their hives – not a natural bee keeper’s modus operandi in my opinion.
I have been using Warré hives since 2009 and never had a ‘blow down’ in gales even with 5 box hives. Bees do propolise the boxes together and the weight of occupied boxes gives stability. A good firm base is essential for stability and a sheltered location helps.
Colonies occasionally build brace comb from combs in one box to the top-bars in lower boxes. If you need to separate boxes, it is sometimes necessary to slide a ‘cheese-wire’ between boxes to cut this brace comb. Lugs and projections would prevent this.
I would not advise the use of lugs or projections to locate boxes. You could could screw side bars to the outside of boxes and use ‘guy ropes’ or straps to anchor hives if worried.
John, Stockbridge Hants
A warre was blown over this winter in my area. Don’t know how full it was but the bees were on the grass and everything was in a right old mess. Anyway the bees were scraped up by hand and put back in the hive. They have gone on to be brilliant bees this year so no harm done. However, the beekeeper is putting posts around the hive and using straps to stop it happening again.