I will check the timber type the next time I pass bye the cottage but I suspect that as per most modern gates of this type which are found widely across England today that these tend still to be made from oak and not tropical hardwoods. This cottage is located in quite a shaded damp spot and so the colour apparent on this gate is mould. You raise an interesting point as to whether or not all features on a historic site should replicate former patterns and practices but to what date should these comply ?
The simple answer to your question about windows and glass is that this type of building predates the use of glass and so any wind hole openings would have been fitted with wooden mullions and sliding shutters. These were located above and below the gable end cross beam and are now covered by the attached chimney (see article sketch).
The chimney employs thin tudor bricks and it has been built to follow the already badly deformed profile of the gable.
The front sill is 10 inched higher than the rear sill and this is because the original sill must have rotted out and been replaced. Evidence of this can be seen high up on the front wall centre post where a "scotch" has been cut into the post to facilitate prop jacking of the whole building using a Spanish windlass.
The gable corner post has rotted off and is now underbuilt with brick and has also had a splint stud added.
The cottage originally had wattle & daub infil external panel walls with these later being knoocked out and replaced with brick. The internal cross frame walls are stil wattle & daub.
A low doorway at the front is now blocked with brick and this is opposite an extant rear door forming a good thru draft for this attached kitchen hall.
The oriel dormer window in the cruck end of the roof is a later insert doubtless done when the cruck hall was floored over after the addition of the box framed kitchen hall.