10 Minutes of Portal Prelude

Portal Prelude is a fan-based MOD created to tell the story of Aperture Science's testing facilities before the invention of the all-knowing and loving supercomputer Glados.

In the first 10 minutes of the game, Portal Prelude does two things wrong:
1) It stammers on itself by using unnecessary dialog to prolong play time.
The game starts out the exact same way as Portal does; you wake up in the isolation (relaxation) chamber, ready to go out and conquer this world of white. But Portal Prelude mars the introduction of its game for one reason: the lengthy dialog sequence.
Portal (not Prelude) introduces you to the game by having Glados provide you with a brief synopsis of your state and what you are supposed to do. If my memory serves correctly, this is done in less than a minute or so.
Portal Prelude however, decides to use two (European accented) scientists as your observers, and they yammer on endlessly about extraneous (and unfunny) material for what seems like an eternity before you are allowed to exit the test chamber. They ramble on about some kind of test procedure, your goals, and everything else, but none of it is really necessary--assuming you have played Portal (not Prelude!). They also continue to do this--unnecessarily--before every succeeding test chamber--which for the first ten minutes only counts as the next test chamber.
The general rule here, is you want to use the minimum amount of dialog as possible, in order to get the player playing the game, and not reading a book or watching a movie. Every line of dialog should contribute to some kind of story or atmosphere, and Portal Prelude fails to do this.
2) The game forces you to use a complex gameplay mechanic, and imposes death on the player much too early, allowing frustration to set in and perhaps cause some people to quit the game.
The game crawls along to the first test chamber and gives you the first version of the Aperture Science Handheld Portal Device which can only shoot orange portals, and leave you at the mercy of wherever the game desired to put the blue portal.
In the first test chamber, you are stuck in a square room, enclosed by glass walls, and required to jump out with an orange portal. The trick here is: the blue portal--which you cannot move--is situated in the center of four laser turrets, all of which can kill you. Thus, you are left as the player, to use the orange portal in only way one possible (because you have to shoot it on the wall next to you to exit the room) to get yourself killed because you can't move the blue portal.
Portal Prelude happily throws you into the first test chamber where the majority of players will frustratingly die about 5 times before figuring out the puzzle which requires you to use a gameplay mechanic only introduced in the second half of Portal (NOT PRELUDE).

It would be understandable to take a slightly different course than that of Portal (not the prelude), but starting the first test chamber on such a high ramp of difficulty is not engaging or fun--just frustrating if you don't "get it."