first of all:"great work". I needed rgba transparency for a project of mine and would like to share my results with you. Maybe you want to add this feature in a future release.
I've done some changes in the parsing.Css.class.php on line 151, 198, 1628 and 1669. Also I added some lines to the html2pdf.class.php on line 1536.
It's woking just fine for me.
Fichier joint : html2pdf.class.php Fichier joint : parsingCss.class.php