In i13_road_pack.plugin:

io.blueflower.stapel2d.util.json.JSONException: Names must be strings, but 40 is of type java.lang.Integer at line 6, char 23. Excerpt:
  "category": "$cat_i13_rh_full_road00",
  "sidewalk size": 0,4--ERROR->>>0,

Full source:  [{
    "id": "$i13_rh_full_road00",
  "title": "(RH) Full Sidewalk Road",
  "text": "Right handed full sidewalk road.",
  "category": "$cat_i13_rh_full_road00",
  "sidewalk size": 0,40,
  "sidewalk offset": 0,25,
  "frames": [{ "bmp": "assets/constr_road.png" }, { "bmp": "assets/constr_road.png" }, { "bmp": "assets/constr_road.png" }, { "bmp": "assets/full_road00.png", "x": 64, "w": 32, "count": 1 }, { "bmp": "assets/constr_road.png" }, { "bmp": "assets/full_road00.png", "x": 0, "w": 32, "count": 1 }, { "bmp": "assets/constr_road.png" }, { "bmp": "assets/full_road00.png", "x": 320, "w": 32, "count": 1 }, { "bmp": "assets/constr_road.png" }, { "bmp": "assets/full_road00.png", "x": 256, "w": 32, "count": 1 }, { "bmp": "assets/constr_road.png" }, { "bmp": "assets/full_road00.png", "x": 416, "w": 32, "count": 1 }, { "bmp": "assets/constr_road.png" }, { "bmp": "assets/constr_road.png" }, { "bmp": "assets/constr_road.png" }, { "bmp": "assets/full_road00.png", "x": 288, "w": 32, "count": 1 }, { "bmp": "assets/constr_road.png" }, { "bmp": "assets/constr_road.png" }, { "bmp": "assets/constr_road.png" }, { "bmp": "assets/full_road00.png", "x": 192, "w": 32, "count": 1 }, { "bmp": "assets/constr_road.png" }, { "bmp": "assets/constr_road.png" }, { "bmp": "assets/full_road00.png", "x": 96, "w": 32, "count": 1 }, { "bmp": "assets/full_road00.png", "x": 320, "w": 32, "count": 1 }, { "bmp": "assets/constr_road.png" }, { "bmp": "assets/constr_road.png" }, { "bmp": "assets/full_road00.png", "x": 32, "w": 32, "count": 1 }, { "bmp": "assets/constr_road.png" }, { "bmp": "assets/constr_road.png" }, { "bmp": "assets/constr_road.png" }, { "bmp": "assets/full_road00.png", "x": 352, "w": 32, "count": 1 }, { "bmp": "assets/full_road00.png", "x": 256, "w": 32, "count": 1 }, { "bmp": "assets/constr_road.png" }, { "bmp": "assets/constr_road.png" }, { "bmp": "assets/constr_road.png" }, { "bmp": "assets/constr_road.png" }, { "bmp": "assets/constr_road.png" }, { "bmp": "assets/full_road00.png", "x": 384, "w": 32, "count": 1 }, { "bmp": "assets/full_road00.png", "x": 224, "w": 32, "count": 1 }, { "bmp": "assets/constr_road.png" }, { "bmp": "assets/constr_road.png" }, { "bmp": "assets/constr_road.png" }, { "bmp": "assets/constr_road.png" }, { "bmp": "assets/constr_road.png" }, { "bmp": "assets/full_road00.png", "x": 160, "w": 32, "count": 1 }, { "bmp": "assets/full_road00.png", "x": 384, "w": 32, "count": 1 }, { "bmp": "assets/full_road00.png", "x": 352, "w": 32, "count": 1 }, { "bmp": "assets/full_road00.png", "x": 192, "w": 32, "count": 1 }, { "bmp": "assets/constr_road.png" }, { "bmp": "assets/constr_road.png" }, { "bmp": "assets/constr_road.png" }, { "bmp": "assets/constr_road.png" }, { "bmp": "assets/constr_road.png" }, { "bmp": "assets/constr_road.png" }, { "bmp": "assets/constr_road.png" }, { "bmp": "assets/constr_road.png" }, { "bmp": "assets/constr_road.png" }, { "bmp": "assets/full_road00.png", "x": 128, "w": 32, "count": 1 }, { "bmp": "assets/full_road00.png", "x": 416, "w": 32, "count": 1 }, { "bmp": "assets/full_road00.png", "x": 416, "w": 32, "count": 1 }, { "bmp": "assets/full_road00.png", "x": 288, "w": 32, "count": 1 }, { "bmp": "assets/full_road00.png", "x": 384, "w": 32, "count": 1 }, { "bmp": "assets/constr_road.png" }, { "bmp": "assets/full_road00.png", "x": 224, "w": 32, "count": 1 }],
  "animation": [{ "id": "$i13_anim_two_points_separator00", "x": 19, "y": -6 }, { "id": "$i13_anim_two_points_separator00", "x": 27, "y": -2 }, { "id": "$i13_anim_two_points_separator01", "x": 2, "y": -2 }, { "id": "$i13_anim_two_points_separator01", "x": 10, "y": -6 }, { "id": "$i13_anim_four_points_separator00", "x": 1, "y": 0 }, { "id": "$i13_anim_four_points_separator00", "x": 24, "y": -3 }, { "id": "$i13_anim_four_points_separator01", "x": 10, "y": -7 }, { "id": "$i13_anim_four_points_separator01", "x": 15, "y": 4 }],
  "frame animation indices": [[], [], [], [], [], [], [], [6], [], [0, 1, 2, 3], [], [], [], [], [], [6], [], [], [], [2, 3], [], [], [], [], [], [], [], [], [], [], [4], [4], [], [], [], [], [], [], [], [], [], [], [], [], [], [7], [], [7], [], [], [], [], [], [], [], [], [], [], [], [5], [0, 1], [], [], [5]],
  "dirs": [0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 1, 1, 0, 0, 0, 0, 0, 0, 1, 1, 0, 0, 0, 0, 2, 0, 1, 1, 2, 0, 2, 0, 0, 8, 0, 9, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 8, 1, 9]
,
  "type": "road",
  "author": "ian`",
  "price": 200,
  "monthly price": 3,
  "level": 2,
  "speed": 2,
  "draw ground": true,
  "one way": true,
  "auto join": false,
  "connectable": false,
  "hide id": true,
  "final": true,
  "once": true,
  "allow road crossing": false,
  "requirements": [{ "type": "RANK", "lvl": 5 }]
}]