Since Bibber isn't releasing the optional new Uprising units, I decided to go for those ones and I have finally done it with some of Bibber's help. The only units I did not mod and extract their assets are Izumi and Dr. Shimada.

Here are the full source codes for the Soviet Ursa Major (Giant War Bear) and the Chief Scientist. Both have working animations and sound taunt files. The full source code for the Yuriko Omega has an alternative shader textured model on her secondary ability.
http://www.filefront.com/15671457/ChiefScientistMod.rar
http://www.filefront.com/15663383/GiantWarBearMod.rar
http://www.filefront.com/15730773/YurikoMod.rar


Note that:
1) The Ursa Major is still using the original portrait icons from the Soviet War Bear. For the weapon, DamageType changed from MELEE to EXPLOSIVE, DamageFXType changed from SOVIET_BIGBEAR to ALLIED_DOG (since SOVIET_BIGBEAR cannot be defined) and RadiusDamageEffects only applies to enemies and neutrals. Unit originally costs 10000 (most expensive infantry in the C&C series) and it can attack anything except air units. There is no unit intro video for this unit.
2) The Chief Scientist is supposed to be the 12th new unit in RA3 Uprising but the unit isn't meant to be built for the Soviet Campaign. This is the medic unit for the Soviet and Neutral factions and it does not equip with a weapon. The unit also does not have a created voice taunt when the unit is created. The only attribute modifier that doesn't work for this unit is ShowDebugCircle since it's used in Uprising.

Screenshots: