वैयाकरण सिद्धान्त कौमुदी (भट्टोजि दीक्षित - बालमनोरमा व तत्त्वबोधिनी टीका सम्पूर्ण पूर्वार्ध)

त्व before भ: च् -> क् -> ग्! So अनेकाग्भ्यो is grammatically regular sandhi for अनेकाच् + भ्यः!).
Yes! च् becomes क्, and before voiced भ् it becomes ग्: अनेकाग्भ्यः! Excellent!

Line 27:
वार्तिकमदृष्ट्वैव प्रागूजातत्वेन - wait!
Is it प्रागूजातत्वेन?
Look at प्रागू: it has ग with ू? Or प्राग्जातत्वेन?
Look at the mark under ग्: it's a virama!
Wait, in old fonts virama looks like a small slant or hook, often resembling a small line under the letter: प्राग्जातत्वेन.
Wait, in line 25: लोडूविषयत्वात् - wait, let's look at the virama under ड्/ट्!
Ah! In old fonts, halanta (virama) is a short diagonal stroke under the letter, which can look like ू!
Let's check लोट् in line 25:
तस्य लोट्विषयत्वात्!
Look at the letter: it is ट् with a virama below it!
Because "क्रियासमभिहारे द्वे" is for लोट् (लोटो हिस्वौ वा च तद्ध्वमोः)!
So it is definitely `लोट्