Thanks very much for all the positive feedback, guys!
@PatrickWR: Hahahahah!!! Thanks for the compliment and your comment made me smile. To be honest, I've been playing Second Afghan War colonials for more than three decades, so I doubt I'll ever have my fill, but that being said I agree the rivers and swamp could be very useful for a bunch of other periods and locales, from Biblical to Modern, and from Southern Europe to the Old West. A good gaming buddy may be visiting soon and I suggested he bring some of his French Indochina figures to set up in and around the swamp and take some pics.
At some point after I'm completely done with this layout, I hope to cut up some British and Afghan figures at the waist, paint them, glue them onto thin clear plastic bases, texture the bases with a touch of resin or gloss medium or gel tinted to match the water and use them for river-crossings, swamp ambushes, etc.
@custosarmorum: the color you see all comes from the painted riverbeds and swamp basin, though I plan to tint the next resin pour. The experts all seem to agree that pouring a first layer of clear resin adds greater depth to the tinted coats above. Something to do with light refraction.
I mixed the colors for the water myself, using artists acrylics from an Aaron Brothers art supply store. The foundation was mixing black and yellow ochre to get a nice drab olive green, then adding a hint of brighter green and a little blue. The center of the rivers (where the water's meant to be deeper) got a darker and more vibrant shade while the areas near the riverbanks got the drab and "muddy" shade more suited to the shallows.
Here's a pic showing the painted river before adding resin…
If you'd like more info, here's a link to an earlier blog post I did about painting the water:
link