Unresolved First few attempts with PETG miserable . . .

Attempting to print a case for Smart LCD https://www.thingiverse.com/thing:1506387
and having some issues.

First one is, as loaded, the part displays in MC at about a 45 degree angle from the bed. I've seen this before and have simply rotated the part to an orientation that looks rational, to me and print away.

So, I rotated this one to sit "face down" on the bed and printed one try in PLA. Worked well, to my astonishment, but, sadly, once I removed it from the bed, it was bowed. Oh, well, the designer did sat to use PETG pr ABS.

I guess the question there is, am I doing the right thing, or should it print "as presented" and select supports of some kind, as it seems impossible to print otherwise.

So, I went with PETG since I have several spools of that laying about. But, I find, other than adhesion issues (odd since it is claimed PETG is better than PLA in that regard), but, with extruder temp at 245, I seem to be getting some stringing during auto level and while printing.

What I have turned up suggests the extruder is "too hot", but at lower temp I got some "beading" in the first couple perimiters (?) so turned it up a bit.

Suggestions? FWIW, ALL the filament I have is of unknown age, having been purchased at an estate sale along with the printers.

 

I continued to have issues with corners curling up, so I reverted to PLA and a simpler print for a test. It lifted almost immediately.

Confounded, I then realized I was printing with no skirts as I thought was suggested by the designer.

As I poked around a bit more I found a design on thingiverse I like a lot better that features simpler pieces, and does not recommend PETG. So for now I will go with that and come back to PETG efforts once I get that done.