The Bog Slain that i converted (much help from the folks on this forum, of course) should be found in Monster Geographica: Marsh and Aquatic - don't have a link available, though it is being sold in PDF format. i just completed a bunch of monsters from the Penumbra Fantasy Bestiary for the MG: Forest volume. i haven't converted the others you mentioned.
in the meantime, here are the stats as complete as they were when i sent them to the editor:
Bog Slain
Medium Undead
Hit Dice: 6d12 (39 hp)
Initiative: +0
Speed: 30 ft. (6 squares), swim 20 ft. (4 squares)
Armor Class: 16 (+6 natural), touch 10, flat-footed 16
Base Attack/Grapple: +3/+4
Attack: Slam +4 melee (1d6+1)
Full Attack: Slam +4 melee (1d6+1)
Space/Reach: 5 ft./5 ft.
Special Attacks: Breath weapon, disease
Special Qualities: Damage reduction 5/slashing or piercing, darkvision 60 ft., resistance to fire 10, undead traits
Saves: Fort +4, Ref +2,Will +6
Abilities: Str 13, Dex 10, Con —, Int —, Wis 12, Cha 3
Skills: Swim +9
Feats: Great Fortitude B
Environment: Cold marsh
Organization: Solitary, gang (2-5), squad (6-10), mob (11-20)
Challenge Rating: 4
Treasure: Standard
Alignment: Always chaotic evil
Advancement: 7-18 HD (Medium)
Level Adjustment: —
Bog slain are the bloated, waterlogged corpses that rise from the site of their demise—the peat bogs of colder climates. Stained by the dark mud of the bog and perpetually dripping peaty water, bog slain have one objective: to seek and destroy life. Some scatter throughout the swamp, killing game and the passerby, while others swarm towards villages and communities.
Combat
A bog slain can hold water in its lungs and stomach, which it uses to spew gouts of foul water from its mouth to batter its foes.
Breath Weapon (Ex): 60-foot line, once every 1d4 rounds, checked for one round and disease (see below), Reflex DC 13 negates. The save DC is Constitution-based. A bog slain can only use its breath weapon three times before needing to submerge in water again to replenish its water reserve. Replenishing the breath weapon takes two full rounds for each time the bog slain has used the ability since last refilling.
Disease (Ex): Blinding sickness—breath weapon, Fortitude DC 13, incubation period 1d3 days, damage 1d4 Str. Each time a victim takes 2 or more points of Strength damage from the disease, he must make another Fortitude save or be permanently blinded. The save DC is Constitution-based.
Skills: A bog slain has a +8 racial bonus on any Swim check to perform some special action or avoid a hazard. It can always choose to take 10 on a Swim check, even if distracted or endangered. It can use the run action while swimming, provided it swims in a straight line.
(the editors wanted the CR to match the HD, so instead of lowering the CR, they had me raise the HD. if you want to bring the HD back down to where it was in the original book, just make sure to lower the CR.)
