Because most people will read from the front, I decided to start from the back for us to cover the whole book.
Back Cover
"the razor edge of space, marine"
Should be "Marine" with a capital M, because it is a few lines down, and elsewhere in the book.
Mission 7: Operation Octopus Garden
p 332, upper left: "But we do have one small problem marines"
Should be "problem, Marines", add a comma and a capital M.
p 332, lower left: "the Black Guard’s Captain Karambit"
Should be "Blackguard's" in one word, according to elsewhere.
p 332, lower left: "Sargeants Seax and Lance"
Should be "Sergeants" with an e.
p 333: "AS-19D Bearcat Strikeships"
p 336: '"D" model Bearcat VTOL Strikeship'
p 339: "AS-19 D Bearcat VTOL Strikeships"
Pick one version. One option is to write the full name "AS-19D Bearcat VTOL Strikeships" at the first mention in the mission, and then "AS-19D Strikeships" in the rest of the chapter, or the full title all the time. Just make sure it uses consistent spacing.
p 342, left: "Xenomorph Goreburster (page 177) Pink slime trails"
Missing period after "(page 177)".
p 343, left: "entire sublevel here They"
Missing period after "here".
p 343, left: "bug-out duffle bag"
p 351, left: "her bug out bag"
It says "bug-out" with a hyphen, and then without. I suggest adding a hyphen on page 351.
p 344, Lyndon box: "ES-4 Pistol"
p 344, DeRosa box: "ES4 Pistol"
Written with hyphen in one place and not in the next. I saw ES4 elsewhere, so perhaps that's the correct term?
p 344, all three boxes: "wrist-worn" and "wrist worn"
The first two boxes without a hyphen, and the third with a hyphen. I suggest adding a hyphen to the first two boxes.
p 347, Processing: "this arm retrieves ovomorphs"
"ovomorphs" with a small o, when it's written with a capital O elsewhere. Change to "Ovomorphs".
p 348, top left: "western Slopes"
"western" with small w, but capital W elsewhere. Change to W.
p 348, left: "vegetarian-choked sinkhole"
Perhaps it should be "vegetation-choked", otherwise I don't know what it means.
p 348, right: "illuminating a sea of ovomorphs"
Should have capital O. If possible, and if it's correct, perhaps search the whole document for this word? Unless there's a difference between upper and lower case versions of the word.
p 349, top left: "3WEF90 Assault Rifles"
p 349, box: "F903WE Assault Riflfle"
If these are the same, pick the correct term.
p 350, right: "its on a collision course"
It should be "it's" with an apostrophe.
p 352, left: "Hyperdyne Corporation lawyer’s up"
It should be "lawyers up" without an apostrophe.
p 352, quote: "CARTER J BURKE"
Add period after "J". Compare with John F. Kennedy and George W. Bush. Also, the Alien Anthology wiki says "Carter J. Burke".