Let's check them case by case:
Estoy tan amandolo.
You can't use tan before a gerund, so you must put it at the end instead. This forces you to use tanto, instead of the tan apocopation.
On the other hand, "Estoy amándolo" sounds a bit odd to begin with, as you'd probably say "Lo amo" on a normal context.
Correct form:
Lo amo tanto.
Estás tan cogido.
This is actually fine. Just take into account that cogido is a regionalism, and in Spain it wouldn't mean what you expect.
For Spain, you would use:
¡Estás tan jodido!
Este tan no está bueno.
This is the hardest one. You can't use tan before a negative, so the only correct variation with "tan" here would be something like: "Este no está tan bueno", but it would have the opposite meaning of what you wanted (ie: instead of "This is so not good.", it would mean "This is not so good.").
The best option for this one would be to change the phrase so you don't need the no. For example:
Esto está tan malo.
Finally, to answer dockeryZ's edit,
¡Esta comida está tan rica!
is commonly used, at least in Spain.