Venerable Bhante Sumana,

Please try the following link
http://www.tipitaka.org/romn/

You cannot download the whole lot at once, but will have to go step by step.

First, you will find the following on the left side of the page.
Tipitaka (Roman)
Tipitaka (Mula)
Atthakatha
Tika
Anya

Please click on Tipitaka (Mula), and you will find:
Vinayapitaka
Suttapitaka
Abhidhammapitaka

Please click on Vinayapitaka, and you will find:
Parajikapali
Pacittiyapali
Mahavaggapali
Culavaggapali
Parivarapali

Please click on Parajikapali, and you will find:
Veranjakandam
1. Parajikakandam
2. Sanghadisesakandam
3. Aniyatakandam
4. Nissaggiyakandam

Please click on 1. Parajikakandam, and you will find:
1. Parajikakandam on the right side of the page.

You can then copy the text on the right side of the page and paste it on.
You have to copy the whole text that appears on the right side, not a portion of it.

In this way, you can go on, one by one, what is listed on the left side.

Respectfully,
Han