Possessive Noun and Gerund questions

[WendyH75]

1. Can this structure be valid?

adj + noun + noun

or it has to have adj + noun's + noun

2. Can an adv be used to describe a gerund?

"...because of slightly increasing the size" is this correct?

[Sage Pearce-Higgins]

1. Can this structure be valid?
adj + noun + noun

In your analysis, would 'a big car park' qualify as "adj + noun + noun"?

2. Can an adv be used to describe a gerund?

It seems possible. I can say 'Eating is enjoyable.' but I can also say 'Eating slowly is enjoyable.'

"...because of slightly increasing the size" is this correct?

This sounds odd to me, but I'd really need to see it in context to make a useful comment.