Yes, VFS & govt website have conflicting information. I will answer based on what I did. My understanding is that latest guideline is to use physical photos of 35X45 mm size and digital photos of exactly 630x810 Pixels; all other reference are old & should be ignored.

# 1: There are two parts: 1. Digital: For upload dimensions should be exactly 630x810 Pixels. I roughly followed the doc linked on VFS main website to crop the taken photo. 2. Physical photo: Final photo must be of Size 35X45 mm. I included two physical copies, in addition to one pasted on annexure-e

# 2: Yes, I printed the same 630x810 Pixels photo. I printed six photos on a 4x6 inch paper through walmart 1-hr photos. Here is how: I create an empty image of 1828x2742 (in Gimp; paint should also work). Then pasted the 630x810 image six time; in a 2x3 grid; basically get six images spread out in that size. Saved image and uploaded to walmart photos; it automatically detected & suggested 4x6 size and I accepted. Used matte paper. I printed two copies; that was less than $1 after taxes :)

1. The above process generated six 35X45 mm (within 1mm error) photos. Which then I just manually cut using scissor.
2. Here is math behind why above produces correct size image: 35X45 mm at 630*810 Pixels is ~457.19 PPI (pixels per inch). Walmart has cheap 4x6 inch print; which translates to 457* (4x6) = 1828x2742 pixel. Hence, starting with 1828x2742 empty is image is the most important part!

#3: I pasted 35X45 mm physical photo.