I found many bugs and errors in AI Mode. Where should I go to report this?
You can post them here or on our discord. Please make sure to provide as much detail as possible.

Note: These kind of errors or bugs can only be happened in AI Mode not in Hand Test. So you need to Duel AI not using the Hand Test feature.

Wait... New Client is up. I'm gonna test the errors in the latest patch and confirm later.
Altergeist Multifaker
Can't trigger Special Summoning while activating already face-up Personal Spoofing on the field. I strongly believe such condition doesn't count as Misses the Chance.

Note: Personal Spoofing is already face-up on the field. I'm not activating a Set Position Personal Spoofing.

According to the Card Ruling:

This card has great synergy with "Personal Spoofing". Repeated use of this interaction can get whichever Altergeist is needed, whenever.
Later in a Duel, revive this card with "Altergeist Manifestation", and chain Spoofing's effect to shuffle away Manifestation. This will get this card's Special Summon and Spoofing's search at next to no cost.

Unfortunately, due to the bug/error I can't repeatedly use Personal Spoofing to Special Summon Altergeist Multifaker.

Tested in both Hand Test and AI Mode.
You are not activating a Trap Card, you are activating a Trap Card's Effect. Therefore you can not use the effect of Altergeist Multifaker.

The synergy works as you activated a Trap Card, Altergeist Manifestation.

How about Altergeist Silquitous's effect being unable to return any Set Position Altergeist Trap card?

Since when card in our Control need to be in face-up position? Set Position card in our field should be considered as card in our possession/control. Is this related to Master Rules 5?
Red-Eyes Dark Dragoon
Whenever I activated Effect Negation during Damage Step, I didn't gain 1000 Atk. Again, is this related to the Rulings?

"Return that card to the owner's hand" When activating the monster effect, the cost is "Altergeist. Return 1 face-up card named "Altergeist" on your field other than "Silquitas" itself to the owner's hand.
If it is face-down how does your opponent know you are returning an Altergeist card?

Red-Eyes Dark Dragoon works fine for me. Note you must destroy the card with Red-Eyes Dark Dragoon's effect to gain the 1000 attack.

Also none of these issues you have brought up are things that would only occur in A.I so please make normal reports in the Card Bug section for more issues.
Ah... I see. Thanks for the explanation.

Red-Eyes Dark Dragoon's negation effect is indeed destroying the card it's negated. Is there a limitation for card to be considered as destroyed?

I'm gonna post a Save Replay for it... Wait...

Edit: I dunno why I can't Attach a Save Replay to this Post. It's forever stuck in the Upload Screen and never complete.

The condition is:
Red-Eyes Dark Dragoon is negating Ash Blossom & Joyous Spring's effect. Ash Blossom is indeed being sent to the Graveyard 1st in Chain to the activation of Dragoon's negation effect. Does Ash Blossom already been in the Graveyard doesn't classify as being destroyed thus make my Dragoon unable to gain 1000 Atk Boost?
Cards already in the Graveyard and banished cards cannot be destroyed.
Alright. Thank you very much, Steel for your answer and help.

It seems most of my problems are about Card Rulings. I'll post more questions in Card Bug section next time.