I learned elsewhere that in 81 pad vastu the East falls between E4 and E5. Is that right?
No. In 81 pad vastu exact East falls on E5 (Surya); East between E4 and E5 belongs to the 64 pad grid, so correct it. The reference is in Vishwakarma Prakash, with the page number given in the previous class; the Hindi translation from Sanskrit by Krishna Kumar Jugnu of Udaipur and the edition of Maharshi Abhay Katyayan give the same.
Related questions
The North-East is the most sacred direction, so why should the main door not be opened at E1, the pada of Shikhi devta?
Because it is the most sacred and pure place, entering there with shoes and slippers is a serious problem. Shikhi devta, who sits at E1, then produces his fire, and his anger brings agni bhay (fear of fire), a greater chance of fire breaking out in the house. So E1 should not be used for the main door, even though people commonly praise it.
Are the 32 outer devtas drawn in the Manushya bhoomi or in the Pishach bhoomi?
In the Pishach bhoomi, the outermost band. The 32 outer devta lines are drawn only within the Pishach bhoomi, while the 12 inner devtas sit in the combined Manushya and Dev band and Brahma in the centre.
Can a nandavart dwar be made in a flat?
Yes, it can be made in a flat too.
Can doors be opened anywhere by vastu, or must the birth chart be checked?
Check the birth chart. If the Sun in the chart is debilitated and you forcibly open an E3 or E4 door, it will be wrong and not appropriate at all.
How are the 64 pad grid and the padas of each devta worked out?
Every pad grid divides the plot into equal sections, for example 81 equal sections for the 81 pad grid; the number of padas each devta occupies is then assigned within that grid. Drawing the devtas by hand will be taught practically in the 81 pad class.
How do we find N1 to N8 and the other door padas on a map?
Use the zoning chakra shown on the first day, or draw it: from the centre of the map draw the four directions 90 degrees apart and the corner directions at 45 degrees, then halve again to 22.5 degrees and once more to 11.25 degrees, which gives 32 padas (360 degrees shared by the 32 guardian devtas). Starting from E1 next to the North-East line, go round clockwise from E1 to E8, then S1 to S8, W1 to W8 and N1 to N8, on the 81-pada grid. Practise this as homework.