Early Varangian Guard? Also question about Armored Spearmen.

In the unit file I came across an entry for Early Varangian Guard. As a Byzantine player, I've never heard of this unit. I added FN_Byzantine to make it playable, yet it won't appear in the Early Period. Why is this?

I added FN_Byzantine for Armored Spearmen, yet they won't appear for my faction even when I'd built the requisite spearmaker level 2. Am I doing something wrong?

Also, why don't added/modded units appear in the custom battle generator? I had set Byzantine Lancers for All_Periods, yet they weren't there, though they were in the Late Period campaign.

Don't know about the spearman, but if you use .badgerbunny. in early you can see the early VG. They are much cooler looking imo