The FS2 Conversion Codex is missing the Pocket Demon from Thorns of the Lotus and Sun Chen from Blood of the valiant.
See this link as the Atlas printings of those 2 products had some errata concerning them:
atlas-games.com/fengshui/fengshui1errata.php
Also, whoever did the conversion did not take into account that some of the 1st edition characters had stat block errors in a few cases the conversions have errors.
For example on a quick look I notice these:
The damage for the Buro Godhammer and Buro Hellharrower are wrong in the conversion on pg. 2.
In the 1st edition FS rules the damage for those 2 weapons is incorrect in the 1st edition stat block.
Also the Ganrled Marauders, The reconstructed, Hopping Vampires, and Snake Men are to be treated as named characters in 1st edition FS. Robin got asked about this on the old FS mailing list.
The Bouncing Benjis claws are damage 15 not damage 11 in 1st edition. The SNF stat block had that error, but the stat block for the them in IYFA had the correct damage of 15 for them.
The damage given for them on page 68 of the conversions was done using the incorrect damage and is too low.
In correct damage listed for claws and hand to hand weapons (punches, kicks, etc. ) were common errors in 1st edition FS stat blocks and show up on several other characters in 1st edition products. (In most cases the person forgot that each level of Abysmal Spines add 2 to the damage. So you add STR +1 for a punch (or default HTH attack which is a punch) and a +2 for each level of Spines (claws).
If the creature can kick with the claws remember that kicks add+2 to damage unlike the default punch.
Another common error in FS edition FS stat blocks is that the weapons (guns mostly) had numerous errors in the stats for them. (These errors were in the descriptions in the core rules, and the know errors on some were never fixed in the 2nd & 3rd 1st edition printings. (2nd printing is the black and white Daedalus one and 3rd is the Atlas version, if you didn't know.)
Jack Donovan is incorrectly called Jake Donovan in GC and the same wrong name error was in the conversion.
GC had a couple of characters with incorrectly spelled names in it.
Tizoc is still missing the acute accent mark over the latter i in his name. This error was introduced in the Atlas version of Blood of the Valiant but it isn't in the earlier Ronin Publishing edition.
Really not sure how the error weren't addressed as during the Kickstarter I did mention the errors in 1st edition products and even sent a word file of them ans posted links in the same email to where all of those corrections were compiled on the Atlas forums for 1st edition stuff.
Also, the FS2 rule book looks like it keep the Atlas edition of the 1st edition FS rules error that removed the Martial Arts of the Magic Cop archetype in it for the same reason.