As you say, if you've successfully spooled film in the darkroom without obvious fogging, then the darkroom is dark enough to print in. Paper only has an effective ISO of about 4, so is much less light sensitive than film.
The problem is your yellow safelight. Multigrade paper is sensitive to both blue light (which gives high contrast) and green light (which gives low contrast). Yellow is a mix of red and green, so it will expose MG paper (in fact, a yellow filter is used for low-contrast printing with MG paper). The safelight was probably intended for use with graded (i.e. single contrast grade) papers that are typically only sensitive to blue light, and would be fine with a yellow safelight.
Like tkamiya I only use 750ml of developer in an 8x10 tray for low volume work (say ten 8x10s) without problems. Working strength developer doesn't keep long so this allows me to replace it regularly without wasting. Like Michael R, I use about 1-1.2 litres of stop and fixer, since these can be reused (I just store them in the fridge between printing sessions).
Last edited by andrew.roos; 07-08-2012 at 01:19 AM. Click to view previous post history.