Infantry mortars are included in the RPG side (ATOW, LosTech: The MechWarrior Equipment Guide, etc.) and as Battle Armor weapons but I can find precious little about them as infantry support weapons for tabletop. There are many questions to answer, so I'll apologize now for the length of this post and also for the pedantic point by point confirmations.
1A. As 2-3-crew weapons (AToW p. 273), each 7 man squad in a normal platoon would be able to use up to two, leading to a standard foot platoon fielding a maximum of eight mortars. Correct?
1B. As crewed weapons, mortars would be support weapons, correct?
1C. Battle Armor mortars, both light and heavy, are listed in Total Warfare (p.217/310 Burst-Fire Weapon Damage vs. Conventional Infantry Table) as dealing 1D6 to conventional infantry. Would this translate to a standard foot platoon with all eight mortars dealing 8D6 to other infantry units?
1D. Both light and heavy mortars are listed in TW p. 305 (Additional IS Weapons and Equipment for BA Table) as dealing 3 damage to non-infantry units. The revised infantry weapon tables for TechManual have light/heavy mortars at 0.53/0.57 each for non-inferno ammo (0.26F/0.34F with inferno). Why the disparity? Other weapons similarly named between BA and infantry or BA and heavy weapons are at least different weights, ranges, etc. indicating they are actually different weapons. This just appears to be a "when carried by infantry" debuff.
2A. Are infantry mortars subject to indirect fire rules for attacks on Tabletop as they are in AToW (p.274)?
2B. There appears to be a range mismatch between heavy BA mortars and heavy infantry mortars. In the revised infantry tables for the TechManual, heavy mortars are listed as having a base range of 3, but Total Warfare (p.305) has heavy BA mortar ranges as a base range 2 weapon. Which is correct? (light mortars are the same in both sources at base range 1.)
2C. Do infantry mortars have a minimum range on tabletop?
3A. Are infantry mortars Area of Effect weapons on Tabletop? (They are listed as AoE in the RPG sources, but many weapons marked AoE in the RPG are not AoE on tabletop.) This matters for infantry on infantry combat where a target may be dug in.
3B. Same for BA, are BA mortars AoE on Tabletop?
4. ATOW (p. 273 and 282-283) lists numerous ammo types that are named similarly to tabletop ammunition types for other weapons. For example, Air-Burst Ordnance for infantry mortars would seem to be the same intent as the specialty Mech Mortar ammo in Tac Ops. However, it doesn't really make sense for the effects to be the same when the 41.67 kg Mech Mortar round is compared to a 2/4 kg L/H infantry mortar round. Likewise, inferno ordnance would be expected to be similar to inferno ammo for SRMs. So the question is which specialty ammunition types are available for Tabletop use and what mechanics they have? I am particularly interested in whichever ammo is considered standard, the anti-personnel ammo (Either air-burst, antipersonnel or ???), inferno, FASCAM, guided, gas/smoke, and flare.