I got an Error about only 0's may be mixed with negative subscripts. I read a txt file as data.frame , it has more than 100 rows with 2 columns. And 4 genes are enriched in hsa04215 pathway. And I extract it from data.frame and transform to a vector, look like
> xx
      836       596      5599     10018 
-7.755529 -3.458985 -2.453181 -1.870450 
> hsa04215 <- pathview(gene.data=xx,
+                      pathway.id="hsa04215",
+                      species ="hsa")
'select()' returned 1:1 mapping between keys and columns
Info: Working in directory D:/desktop_folder
Info: Writing image file hsa04215.pathview.png
Info: some node width is different from others, and hence adjusted!
Error in img[pidx[i, 3]:pidx[i, 4], sel.px, 1:3] :
  only 0's may be mixed with negative subscripts

These days I got an answer from your Pathview web server. Because it has no hsa04215 pathway in your web server. But it has hsa04215 pathway in KEGG website (http://www.kegg.jp/pathway/hsa04215).

In pathview KEGG visualization, setting "same.layer" to FALSE fixed the problem for me.

I have same problem