Hello, i had 2 question about post ads.
 1 ( : How can i add image at preview mode? because when i click preview no had a image . (Please see a first attach file)
 2 : How can i resize a image with same dimension? In post ads, i set 2 image but 1 image with big dimension and 1 image with small dimension. i just want 2 image with same dimension. (Please see a second attach file)

See attach file below for understand what i asking about.
please help me. thank you

@eppolroy
Thumbnails and preview images are generated automatically by osclass when ad is published.
To have images in same dimension, you must change settings in media - Force image aspect.

@epoolroy
why that image not appear? how can i solve this?
You have probably issue with GD/ImageMagick library, try to swap them, check osclass docs.

I already check box but nothing happen... how can i edit a file php if i want edit by manual?
You must regenerate thumbnails after that, check osclass docs for more details.