The third design seems to be based off one of the winners of the competition announced in March. Project 119 (competition code), known as "CRYSTAL". If I understand the translation correctly, it's a Green Water corvette, which can also be classified as a LCS equivalent (LBK or Littoral Battleship[литоральный боевой корабль] in Russian terms). The designer was one Hlutčin Igor Vladimirovich. Based on the category he won, it would appear that he's a professional naval architect. No hard confirmation yet, but it looks like he was hired by USC after the competition, most likely as a designer over at Almaz Central Marine Design Bureau.
EDIT: Just saw your reply Triton, thanks for the compliment.
EDIT2: The more up to date version of the Project 119 entry page that Trition found confirms that the design utilizes a modular architecture. Other details include a baseline armament of one retractable AK-174M mount (possibly a development of the AK-176M-MR-123-02/76 Artillery System, but it doesn't say), together with 6 universal launching towers (VLS's in other words), each containing 8 cells. It's intended air component is, depending on mission/s, either the Kamov Ka-27 Helix or Ka-29 Helix-B, along with several BPLA (general Russian designation for military drones). The page doesn't say if the latter are VTUAVs, other, or a mix. ECM suite includes 4 PK -10 decoy launchers. It would seem to have a much better range of sensor/armament options for it's intended missions than the current LCS classes do.
Has a dash (not substained) speed of 40 knots. CODOG propulsion, albeit with an all-electric transmission?
Correction: COGOG propulsion with diesel backup and all-electric transmission. Interesting design choice.