SNAP error encountered with Sentinel-1 SAR from Google Earth Engine

Question

I have downloaded Sentinel-1 SAR images from GEE in VV and VH polarization. I have two groups of images: 17 images in VV polarization and 17 images with VH polarization.

I have a model that is suppose to correct those images in SNAP:

As you can see, whenever I try to run this I get this error message:

I thought maybe the error is because I have for each image only one polarization mode because my code extract it like this. Or maybe the problem is that I haven't downloaded it directly from Sentinel, however, I have seen many researches that have used GEE to download SAR images.

This is the code I have been using:

var img = ee.ImageCollection('COPERNICUS/S1_GRD')
        .filter(ee.Filter.listContains('transmitterReceiverPolarisation','VH'))
        .filter(ee.Filter.eq('instrumentMode', 'IW'))
        .select('VH')
        .filterDate('2018-01-01','2018-05-01')
        .filterBounds(geometry)
        .map(function(image) {
          var edge = image.lt(-30.0);
          var maskedImage = image.mask().and(edge.not());
          return image.updateMask(maskedImage);
        });

var desc = img.filter(ee.Filter.eq('orbitProperties_pass', 'DESCENDING'));

var dataset=img.size();
print(dataset)

var clippedCol=img.map(function(im){ 
   return im.clip(geometry);
}); 

var listOfImages =(clippedCol.toList(clippedCol.size()));

var listOfNumbers = [0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16];

for (var i in listOfNumbers) {
  var image = ee.Image(listOfImages.get(listOfNumbers[i]));
  var toexport=image.visualize({min: -30, max: 5}).addBands(image);

  // do what ever you need with image
  Map.addLayer(image,{min: -30, max: 5}, i);
  Export.image.toDrive({
  image: toexport.toFloat(),
  description: i,
  scale:10,
  crs:'EPSG:4326',
  maxPixels:1310361348,
  region:geometry.geometry().bounds()});
}

Map.centerObject(geometry)

My end goal is to be able to process my SAR images that were download from GEE.

Additional information: I am able to display those images from GEE, but can't run any analysis, and each image has 2 bands as you can see here:

Edit2 - I thought maybe it doesn't work because the images are corrected already. I have tried to create stack but got the next error message:

Answer 1

The Sentinel-1 SAR data available as GeoTIFFs from Google Earth Engine are already preprocessed and geocoded:

https://developers.google.com/earth-engine/datasets/catalog/COPERNICUS_S1_GRD

SNAP needs the original product structure and metadata to be able to apply SAR-related processing functions.

You can, however, create a stack in SNAP if you select "Product Geolocation" instead of "Orbit" in the stacking module under "Initial Offset Method".